Latency on OC48

Hi
My question is regarding a latency on one of our OC48 transatlantic circuit from new york to london. This circuit has provisioned by a US based carrier. We used to have a 80ms of ping replies and now it has jumped to 110ms.
I investigated and couldn't find any issues with our OC48. I am not seeing any type of sonet errors including Loss of signal and Loss of Light, also Sonet path hasn't been changed either by our Telco, but latency has increased by 30ms. Can someone help me out with this problem.
Thanks

To Swissguy: is 110msec of delay any cause of users dropping data, voice, video between continents, or did you jest notice at one point that ping replies went from 80msec to 110msec and you want ping replies as fast as they can be? If all other aspects (emulated circuits, LANE, whatever) run without problem, I can't understand why you are worried about ping delay. Personally, I'd stop worrying.
To swalimbe: I partially disagree with your statement "There is never latency involved with sonet". In a perfect world I would agree. There are two obvious things: (1) even though OC-38 sonet is a deterministic technology, the layers that ride in it do not have to be. The framer ASICS rely on getting Ethernet or Token Ring frames from buffered memory - that is one source of delay , (packets have to be SARRED & UNSARRED when going onto & leaving ATM). As transistors age, the gain can lessen and turn-on time decrease slightly - adding to delay- over time to the framing process.(2) yes I agree on the routers being probably the main delay source. If they are configured correctly, ping requests and replies get a lower priority than voice & video.
To things like OC-Xs riding inside the OC-48, the OC-X is buffered before being injected to the timeslots of the OC-48 - the injection process feels the same effects of buffering and delay.
Would you not say swissguy has no need to worry if all other users of the OC-48 have no complaints?
Bill

Similar Messages

Latency issue in Desktop Sharing

We are planning to develop a conferencing solution using LCCS. I am trying to evaluate the screen/desktop-sharing application. I am experiencing 5-10 seconds latency during the transfer of the screen data to the other end.
I am using the demo application(ScreenShareSubscriber and ScreenSharePublisher), provided in the SDK.
Some more details:
- Current OS is Windows 7 (32 bit).
- I am behind a proxy.
- I am running the applications in India.
- Using Flex builder 4.6 with Flash player 11.1.
- Using the developer account to test the application.
Questions:
- Can the delay be reduced programatically? If yes, then how?
- The final solution may be used by people distributed across the globe. Is there a possibility that, the latency is affected by your location?
- If the above is true, does Adobe provide cloud services (for commercial applications) that are distributed in different location, to reduce the latency?
- Can proxy server be an issue? We have port 443 open on the proxy server for TSL connections.
- If the above is true, then how can we avoid the issue? The final application may be used in a corporate network and we cannot ask everyone to change their network settings to connect LCCS services.
I have checked some posts on the forum, which say that, the performance is faster on Macs. We are currently not targetting the Mac platform.
Thanks,
Subrat

Hi,
Please double check the following firewall port between two subnets.
Front End Servers-Lync Server Application Sharing service 5065 TCP used for incoming SIP listening requests for application sharing.
Front End Servers-Lync Server Application Sharing service 49152-65535 TCP Media port range used for application sharing.
Clients 1024-65535* TCP Application sharing.
If the issue persists, you can use the Lync server logging tool on FE server to test the process of desktop sharing.
Here is the link of using the Lync logging tool:
http://blog.schertz.name/2011/06/using-the-lync-logging-tool/
Note: Microsoft is providing this information as a convenience to you. The sites are not controlled by Microsoft. Microsoft cannot make any representations regarding the quality, safety, or suitability of any software or information found there. Please make
sure that you completely understand the risk before retrieving any suggestions from the above link.
Best Regards,
Eason Huang
Eason Huang
TechNet Community Support

A quick primer on audio drivers, devices, and latency

This information has come from Durin, Adobe staffer:
Hi everyone,
A common question that comes up in these forums over and over has to do with recording latency, audio drivers, and device formats. I'm going to provide a brief overview of the different types of devices, how they interface with the computer and Audition, and steps to maximize performance and minimize the latency inherent in computer audio.
First, a few definitions:
Monitoring: listening to existing audio while simultaneously recording new audio.
Sample: The value of each individual bit of audio digitized by the audio device. Typically, the audio device measures the incoming signal 44,100 or 48,000 times every second.
Buffer Size: The "bucket" where samples are placed before being passed to the destination. An audio application will collect a buffers-worth of samples before feeding it to the audio device for playback. An audio device will collect a buffers-worth of samples before feeding it to the audio device when recording. Buffers are typically measured in Samples (command values being 64, 128, 512, 1024, 2048...) or milliseconds which is simply a calculation based on the device sample rate and buffer size.
Latency: The time span that occurs between providing an input signal into an audio device (through a microphone, keyboard, guitar input, etc) and when each buffers-worth of that signal is provided to the audio application. It also refers to the other direction, where the output audio signal is sent from the audio application to the audio device for playback. When recording while monitoring, the overall perceived latency can often be double the device buffer size.
ASIO, MME, CoreAudio: These are audio driver models, which simply specify the manner in which an audio application and audio device communicate. Apple Mac systems use CoreAudio almost exclusively which provides for low buffer sizes and the ability to mix and match different devices (called an Aggregate Device.) MME and ASIO are mostly Windows-exclusive driver models, and provide different methods of communicating between application and device. MME drivers allow the operating system itself to act as a go-between and are generally slower as they rely upon higher buffer sizes and have to pass through multiple processes on the computer before being sent to the audio device. ASIO drivers provide an audio application direct communication with the hardware, bypassing the operating system. This allows for much lower latency while being limited in an applications ability to access multiple devices simultaneously, or share a device channel with another application.
Dropouts: Missing audio data as a result of being unable to process an audio stream fast enough to keep up with the buffer size. Generally, dropouts occur when an audio application cannot process effects and mix tracks together quickly enough to fill the device buffer, or when the audio device is trying to send audio data to the application more quickly than it can handle it. (Remember when Lucy and Ethel were working at the chocolate factory and the machine sped up to the point where they were dropping chocolates all over the place? Pretend the chocolates were samples, Lucy and Ethel were the audio application, and the chocolate machine is the audio device/driver, and you'll have a pretty good visualization of how this works.)
Typically, latency is not a problem if you're simply playing back existing audio (you might experience a very slight delay between pressing PLAY and when audio is heard through your speakers) or recording to disk without monitoring existing audio tracks since precise timing is not crucial in these conditions. However, when trying to play along with a drum track, or sing a harmony to an existing track, or overdub narration to a video, latency becomes a factor since our ears are far more sensitive to timing issues than our other senses.   If a bass guitar track is not precisely aligned with the drums, it quickly sounds sloppy. Therefore, we need to attempt to reduce latency as much as possible for these situations. If we simply set our Buffer Size parameter as low as it will go, we're likely to experience dropouts - especially if we have some tracks configured with audio effects which require additional processing and contribute their own latency to the chain. Dropouts are annoying but not destructive during playback, but if dropouts occur on the recording stream, it means you're losing data and your recording will never sound right - the data is simply lost.   Obviously, this is not good.
Latency under 40ms is generally considered within the range of reasonable for recording. Some folks can hear even this and it affects their ability to play, but most people find this unnoticeable or tolerable. We can calculate our approximate desired buffer size with this formula:
(Sample per second / 1000) * Desired Latency
So, if we are recording at 44,100 Hz and we are aiming for 20ms latency:   44100 / 1000 * 20 = 882 samples. Most audio devices do not allow arbitrary buffer sizes but offer an array of choices, so we would select the closest option. The device I'm using right now offers 512 and 1024 samples as the closest available buffer sizes, so I would select 512 first and see how this performs. If my session has a lot of tracks and/or several effects, I might need to bump this up to 1024 if I experience dropouts.
Now that we hopefully have a pretty firm understanding of what constitutes latency and under what circumstances it is undesirable, let's take a look at how we can reduce it for our needs. You may find that you continue to experience dropouts at a buffer size of 1024 but that raising it to larger options introduces too much latency for your needs. So we need to determine what we can do to reduce our overhead in order to have quality playback and recording at this buffer size.
Effects: A common cause of playback latency is the use of effects. As your audio stream passes through an effect, it takes time for the computer to perform the calculations to modify that signal. Each effect in a chain introduces its own amount of latency before the chunk of audio even reaches the point where the audio application passes it to the audio device and starts to fill up the buffer. Audition and other DAWs attempt to address this through "latency compensation" routines which introduce a bit more latency when you first press play as they process several seconds of audio ahead of time before beginning to stream those chunks to the audio driver. In some cases, however, the effects may be so intensive that the CPU simply isn't processing the math fast enough.   With Audition, you can "freeze" or pre-render these tracks by clicking the small lightning bolt button visible in the Effects Rack with that track selected. This performs a background render of that track, which automatically updates if you make any changes to the track or effect parameters, so that instead of calculating all those changes on-the-fly, it simply needs to stream back a plain old audio file which requires much fewer system resources. You may also choose to disable certain effects, or temporarily replace them with alternatives which may not sound exactly like what you want for your final mix, but which adequately simulate the desired effect for the purpose of recording.   (You might replace the CPU-intensive Full Reverb effect with the lightweight Studio Reverb effect, for example. Full Reverb effect is mathematically far more accurate and realistic, but Studio Reverb can provide that quick "body" you might want when monitoring vocals, for example.) You can also just disable the effects for a track or clip while recording, and turn them on later.
Device and Driver Options: Different devices may have wildly different performance at the same buffer size and with the same session. Audio devices designed primarily for gaming are less likely to perform well at low buffer sizes as those designed for music production, for example. Even if the hardware performs the same, the driver mode may be a source of latency. ASIO is almost always faster than MME, though many device manufacturers do not supply an ASIO driver. The use of third-party, device-agnostic drivers, such as ASIO4ALL (www.asio4all.com) allow you to wrap an MME-only device inside a faux-ASIO shell. The audio application believes it's speaking to an ASIO driver, and ASIO4ALL has been streamlined to work more quickly with the MME device, or even to allow you to use different inputs and outputs on separate devices which ASIO would otherwise prevent.
We also now see more USB microphone devices which are input-only audio devices that generally use a generic Windows driver and, with a few exceptions, rarely offer native ASIO support. USB microphones generally require a higher buffer size as they are primarily designed for recording in cases where monitoring is unimportant. When attempting to record via a USB microphone and monitor via a separate audio device, you're more likely to run into issues where the two devices are not synchronized or drift apart after some time. (The ugly secret of many device manufacturers is that they rarely operate at EXACTLY the sample rate specified. The difference between 44,100 and 44,118 Hz is negligible when listening to audio, but when trying to precisely synchronize to a track recorded AT 44,100, the difference adds up over time and what sounded in sync for the first minute will be wildly off-beat several minutes later.) You are almost always going to have better sync and performance with a standard microphone connected to the same device you're using for playback, and for serious recording, this is the best practice. If USB microphones are your only option, then I would recommend making certain you purchase a high-quality one and have an equally high-quality playback device. Attempt to match the buffer sizes and sample rates as closely as possible, and consider using a higher buffer size and correcting the latency post-recording. (One method of doing this is to have a click or clap at the beginning of your session and make sure this is recorded by your USB microphone. After you finish your recording, you can visually line up the click in the recorded track with the click in the original track by moving your clip backwards in the timeline. This is not the most efficient method, but this alignment is the reason you see the clapboards in behind-the-scenes filmmaking footage.)
Other Hardware: Other hardware in your computer plays a role in the ability to feed or store audio data quickly. CPUs are so fast, and with multiple cores, capable of spreading the load so often the bottleneck for good performance - especially at high sample rates - tends to be your hard drive or storage media. It is highly recommended that you configure your temporary files location, and session/recording location, to a physical drive that is NOT the same as you have your operating system installed. Audition and other DAWs have absolutely no control over what Windows or OS X may decide to do at any given time and if your antivirus software or system file indexer decides it's time to start churning away at your hard drive at the same time that you're recording your magnum opus, you raise the likelihood of losing some of that performance. (In fact, it's a good idea to disable all non-essential applications and internet connections while recording to reduce the likelihood of external interference.) If you're going to be recording multiple tracks at once, it's a good idea to purchase the fastest hard drive your budget allows. Most cheap drives spin around 5400 rpm, which is fine for general use cases but does not allow for the fast read, write, and seek operations the drive needs to do when recording and playing back from multiple files simultaneously. 7200 RPM drives perform much better, and even faster options are available. While fragmentation is less of a problem on OS X systems, you'll want to frequently defragment your drive on Windows frequently - this process realigns all the blocks of your files so they're grouped together. As you write and delete files, pieces of each tend to get placed in the first location that has room. This ends up creating lots of gaps or splitting files up all over the disk. The act of reading or writing to these spread out areas cause the operation to take significantly longer than it needs to and can contribute to glitches in playback or loss of data when recording.

There is one point in the above that needed a little clarification, relating to USB mics:
_durin_ wrote:
If USB microphones are your only option, then I would recommend making certain you purchase a high-quality one and have an equally high-quality playback device.
If you are going to spend that much, then you'd be better off putting a little more money into an external device with a proper mic pre, and a little less money by not bothering with a USB mic at all, and just getting a 'normal' condensor mic. It's true to say that over the years, the USB mic class of recording device has caused more trouble than any other, regardless.
You should also be aware that if you find a USB mic offering ASIO support, then unless it's got a headphone socket on it as well then you aren't going to be able to monitor what you record if you use it in its native ASIO mode. This is because your computer can only cope with one ASIO device in the system - that's all the spec allows. What you can do with most ASIO hardware though is share multiple streams (if the device has multiple inputs and outputs) between different software.
Seriously, USB mics are more trouble than they're worth.

Windows Server 2012 Hyper-V network latencies

Hi All,
I have an issue with our Windows Server 2012 Hyper-V hosts that I can't seem to figure out. Situation:
2 x Dell PowerEdge R815 servers with AMD opteron 6376 16 core CPU's and 128 GB RAM running Windows Server 2012 with Hyper-V.
2 virtual machines running on the same physical host and connected to the same virtual switch show high TCP connection latencies. One virtual machines runs a SQL Server 2012 database instance and a Dynamics AX 2012 R2 instance. The other machine a
SharePoint 2013 instance and the AX client. We see latencies of 20ms and higher on most of the TCP connections that are made from the sharepoint machine to the sql server machine.
At first I thought it might have something to do with the physical NIC's. It turned out that VMQ wasn't correctly supported by the firmware of the Broadcom BCM5709c cards. By default this setting is enabled. Turning off the VMQ setting somewhat improved
the situation but the latencies are still at 8ms and higher.
What I don't understand is what influence enabling/disabling VMQ should have on network performance. As I understand it now virtual machines connected to the same virtual switch bypass the physical altogether. Another point is that VMQ should actually improve
performance, not decrease it.
Another question I have is about the various tcp offloading settings on the physical NIC's. After installing the new firmware and drivers from Dell most of these settings are set to disabled. The documents I have been able to find talk about Windows Server
2008, any thought how these settings relate to Windows Server 2012 and whether they should be enabled?
Thanks in advance for your time and thoughts
Kind regards,
Dennes Schuitema

Hi Denes,
Please try to update your BroadCom NIC driver version ,the newest version should be 7.8.51
For details please refer to following link :
http://www.broadcom.com/support/ethernet_nic/netxtremeii.php
Best Regards
Elton Ji
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Mixing Ram with different CAS latencies in K7n2 Delta-L?

I have been using 512mb Kingston Value Ram in my computer, pc3200, with CAS latency of 3.0. I just purchased some Corsair value select 512mb ram pc3200 with CAS latency of 2.5. I know you are not supposed to mix ram with different speeds (like 400 vs. 333) but does it matter if the CAS latencies are different?
I'm running an AMD XP 1800+, K7n2 delta-L, nforce2 motherboard from MSI. Someone at a computer shop told me they tried mixing Kingston 3.0 CAS with Corsair 2.5 CAS, and said his computer wouldn't even post. So I'm wondering if this is an isolated problem, or you will always run into this problem if you mix ram with different CAS latencies.
If anyone has experience with this issue, please share with the board. Thanks!
Chris

The age old question, will the components I bought be compatible ? There are those that have bought identical matching memory that didn't work. In my case, I had an ECS K7S5A that used PC2100 Crucial memory, the sticks neither matched (at one time they did, but one stick died and they sent me the closest thing they had.). Neither of these Crucial sticks was identified by a configurator as being compatible with the K7N2 Delta L that I decided to buy. In the end, not only did both sticks work, but I put them in as single channel mode (ram slots 1 & 2), but later changed the configuration to dual channel mode (ram slots 1 & 3, even 2 & 3). It worked flawlessly in all three configurations. Sorry for the long answer, but in essence, there are no guarantees and your worries will drive you crazy. When memory is mixed, you reduce the likelihood of compatibility, even when you go beyond the recommended products that were specifically identified.
That guy at the computer shop, did he ever indicate or isolate the true reason why the memory wouldn't work ? Maybe, maybe not. I would think with a disparity in memory, the bios is the key to setting the settings for the worst stick of the bunch. Then again, the products you get might overclock to what the better sticks run at. My assumption is that mixed sticks, the bios retards settings to this in "auto" mode. When you force it manually, it may work or it may fail. One thing you oughta know, each and every stick has the manufacturers id encoded onto them at the very least, just like the firmware on other items indicates a manufacturer code and other data that allows these things to be compatible. So know you face that battle going in with any of them. If the bios programming doesn't allow it to work, from that perspective, there'll be problems.

Home wireless router. Awful latency.

Hello guys.
I have a wireless router at home, as all the cool guys in the block. Recently I am experiance an awful latency. I am sitting next to the router, less then a metter from it. Here is what I have:
[ ~ ] netstat -rn
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
0.0.0.0 192.168.10.1 0.0.0.0 UG 0 0 0 wlan0
192.168.10.0 0.0.0.0 255.255.255.0 U 0 0 0 wlan0
[ ~ ] ping 192.168.10.1 -c 10
PING 192.168.10.1 (192.168.10.1) 56(84) bytes of data.
64 bytes from 192.168.10.1: icmp_req=1 ttl=64 time=67.8 ms
64 bytes from 192.168.10.1: icmp_req=2 ttl=64 time=593 ms
64 bytes from 192.168.10.1: icmp_req=3 ttl=64 time=0.749 ms
64 bytes from 192.168.10.1: icmp_req=4 ttl=64 time=96.1 ms
64 bytes from 192.168.10.1: icmp_req=5 ttl=64 time=474 ms
64 bytes from 192.168.10.1: icmp_req=6 ttl=64 time=379 ms
64 bytes from 192.168.10.1: icmp_req=7 ttl=64 time=94.9 ms
64 bytes from 192.168.10.1: icmp_req=8 ttl=64 time=19.4 ms
64 bytes from 192.168.10.1: icmp_req=9 ttl=64 time=76.4 ms
64 bytes from 192.168.10.1: icmp_req=10 ttl=64 time=0.797 ms
64 bytes from 192.168.10.1: icmp_req=154 ttl=64 time=1366 ms
64 bytes from 192.168.10.1: icmp_req=155 ttl=64 time=404 ms
64 bytes from 192.168.10.1: icmp_req=156 ttl=64 time=139 ms
64 bytes from 192.168.10.1: icmp_req=157 ttl=64 time=1564 ms
64 bytes from 192.168.10.1: icmp_req=158 ttl=64 time=1158 ms
64 bytes from 192.168.10.1: icmp_req=159 ttl=64 time=190 ms
64 bytes from 192.168.10.1: icmp_req=160 ttl=64 time=618 ms
64 bytes from 192.168.10.1: icmp_req=161 ttl=64 time=74.7 ms
64 bytes from 192.168.10.1: icmp_req=162 ttl=64 time=395 ms
64 bytes from 192.168.10.1: icmp_req=163 ttl=64 time=1024 ms
64 bytes from 192.168.10.1: icmp_req=164 ttl=64 time=276 ms
64 bytes from 192.168.10.1: icmp_req=165 ttl=64 time=1049 ms
64 bytes from 192.168.10.1: icmp_req=166 ttl=64 time=589 ms
64 bytes from 192.168.10.1: icmp_req=167 ttl=64 time=644 ms
64 bytes from 192.168.10.1: icmp_req=168 ttl=64 time=979 ms
64 bytes from 192.168.10.1: icmp_req=169 ttl=64 time=779 ms
64 bytes from 192.168.10.1: icmp_req=170 ttl=64 time=623 ms
64 bytes from 192.168.10.1: icmp_req=171 ttl=64 time=3450 ms
64 bytes from 192.168.10.1: icmp_req=172 ttl=64 time=13993 ms
64 bytes from 192.168.10.1: icmp_req=173 ttl=64 time=14286 ms
64 bytes from 192.168.10.1: icmp_req=174 ttl=64 time=13286 ms
64 bytes from 192.168.10.1: icmp_req=175 ttl=64 time=12320 ms
64 bytes from 192.168.10.1: icmp_req=176 ttl=64 time=11430 ms
64 bytes from 192.168.10.1: icmp_req=177 ttl=64 time=10586 ms
64 bytes from 192.168.10.1: icmp_req=178 ttl=64 time=10008 ms
64 bytes from 192.168.10.1: icmp_req=179 ttl=64 time=9684 ms
64 bytes from 192.168.10.1: icmp_req=180 ttl=64 time=8809 ms
64 bytes from 192.168.10.1: icmp_req=181 ttl=64 time=7857 ms
64 bytes from 192.168.10.1: icmp_req=182 ttl=64 time=6992 ms
64 bytes from 192.168.10.1: icmp_req=183 ttl=64 time=6610 ms
64 bytes from 192.168.10.1: icmp_req=184 ttl=64 time=6017 ms
64 bytes from 192.168.10.1: icmp_req=185 ttl=64 time=6606 ms
64 bytes from 192.168.10.1: icmp_req=186 ttl=64 time=8064 ms
64 bytes from 192.168.10.1: icmp_req=187 ttl=64 time=7057 ms
64 bytes from 192.168.10.1: icmp_req=188 ttl=64 time=6056 ms
64 bytes from 192.168.10.1: icmp_req=189 ttl=64 time=5123 ms
64 bytes from 192.168.10.1: icmp_req=190 ttl=64 time=4122 ms
64 bytes from 192.168.10.1: icmp_req=191 ttl=64 time=3131 ms
64 bytes from 192.168.10.1: icmp_req=192 ttl=64 time=2220 ms
64 bytes from 192.168.10.1: icmp_req=193 ttl=64 time=1407 ms
64 bytes from 192.168.10.1: icmp_req=194 ttl=64 time=506 ms
64 bytes from 192.168.10.1: icmp_req=195 ttl=64 time=185 ms
This is my wifi on my laptop:
[ ~ ] lsusb
Bus 001 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 007 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 008 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 0a5c:4500 Broadcom Corp. BCM2046B1 USB 2.0 Hub (part of BCM2046 Bluetooth)
Bus 004 Device 002: ID 15d9:0a4c Trust International B.V. USB+PS/2 Optical Mouse
Bus 001 Device 003: ID 413c:8157 Dell Computer Corp. Integrated Keyboard
Bus 001 Device 004: ID 413c:8158 Dell Computer Corp. Integrated Touchpad / Trackstick
[ ~ ]
wlan0 IEEE 802.11abg ESSID:"Fanagoria"
Mode:Managed Frequency:2.422 GHz Access Point: D8:5D:4C:F1:D7:02
Retry long limit:7 RTS thr:off Fragment thr:off
Power Management:off
I have the wl driver:
[ ~ ] lsmod | grep wl
wl 2557291 0
cfg80211 176889 1 wl
lib80211 3949 2 wl,lib80211_crypt_tkip
[ ~ ]
Here is my MODULES section in my /etc/rc.conf file:
[ ~ ] cat /etc/rc.conf | grep MODULES
# MODULES: Modules to load at boot-up. Blacklisting is no longer supported.
MODULES=(lib80211 wl fuse cpufreq_powersave cpufreq_userspace cpufreq_conservative cpufreq_stats cpufreq_ondemand acpi-cpufreq fglrx)
[ ~ ]
My wireless router is that TP-LINK and it`s firmware is updated to the latest version. (I using the stock firmware). There are no wireless network in range, that are using the same channel as mine is. The latency is happening to my friends connected to my router too. I am using wicd for network manager, and wicd-curses for network manager front-end.
I will post more info if needed.
Please advise me what can I do.
Regards
Last edited by Gruntz (2012-05-15 18:46:17)

Okay well I can see nothing that would cause this in anything you've posted. Especially if your friends are experiencing this too.
I would either try downgrading the firmware (If after upgrading this happened). However, I see that your TL-WR1043ND is VERY well supported by Open-WRT. You may want to give it a look.
Remember that the WiFi channels are overlapped. Try getting as far away as possible from other networks.
Ensure you are running WPA-PSK with the AES cipher and a key of 63 pseudorandom characters. This way others are not using your WiFi to torrent and suck bandwidth.
Try to stick to 802.11g but if at all possible go with 802.11n. Also if possible move up to the 5Ghz band to get out of the way of other things using the 2.4Ghz uncontrolled spectrum block.
If your router is running things like DHCP, DNS, FTP, SMB, SSH, NTP, VPN, Etc... Quit it. Your TL-WR1043ND is running a 400Mhz processor with 32Mb of memory.
That's basically all the advice I've got. Hope that get's the ball rolling on fixing this for you.

Safari loading pages slowly / high latency

I have recently been asked by one of my clients to look at a problem with their 3 macs at their place of business. They are an iMac, a macbook and a macbook air. They have all started to exhibit the same problem of being slow to load web pages using safari as their web browser of choice.
Using the broadband speed test at speedtest.net shows that they are getting some extremely high latency (~4000ms) to some sites.
I have tested the broadband connection thoroughly using my own (linux) laptop and everything seems to be in working order. Tests on the macs themselves using a terminal show that latency to the internet and dns response times are all as they should be.
From some limited searching the problem appears to be similar to the problem described in http://discussions.apple.com/thread.jspa?messageID=8799710&#8799710 where safari itself is causing some problems for some reason.
What I'm looking for is some suggestions on how i can go about fixing the problem when i next visit the client

Welcome to the forums!
The following usually works on both Tiger and Leopard:
(First, if yours is an Intel Mac, check that Safari is not running in Rosetta, which is enough to slow it to a crawl.)
Adding DNS codes to your Network Settings, should gives good results in terms of speed-up:
Open System Preferences/Network. Double click on your connection type, or select it in the drop-down menu. Click on TCP/IP and in the box marked 'DNS Servers' enter the following two numbers:
208.67.222.222
208.67.220.220
(An explanation of why that is both safe and a good idea can be read here: http://www.labnol.org/internet/tools/opendsn-what-is-opendns-why-required-2/2587 / )
Whilst in System Preferences/Network you should also turn off 'IPv6' in your preference pane, as otherwise you may not get the full speed benefit (the DNS resolver will default to making SRV queries). If you want to know what IPv6 is:
This is Apple's guidance on iPv6:
http://docs.info.apple.com/article.html?path=Mac/10.5/en/8708.html
Click on Apply Now and close the window.
Restart Safari, and repair permissions.
If that didn't do it, then try this as well:
Empty Safari's cache (from the Safari menu), then close Safari.
Go to Home/Library/Safari and delete the following files:
form values
download.plist
Then go to Home/Library/Preferences and delete
com.apple.Safari.plist
Repair permissions (in Disk Utility).
Start up Safari again, and things should have improved.

Latency issue Logic pro 9.1.3.

Hey,
At the same time as upgrading to Logic from Garageband
I bought a Cakewalk Roland UA25EX ext usb soundcard because i was told
i'd have latency issues if i used the caps lock keyboard for midi
or direct input thru the input jack of
my MacBookPro
(5,3 Intel Core 2 Duo 2.8 GHz)
Sometimes i use the caps lock keyboard to sketch in midi ideas and mostly it's ok.
Other times it's delayed and there's no smile on my face.
When recording with guitars/303/generators DI thru the soundcard
I have latency issues that don't seem to be very regular.
Sometimes it's worse than others.
I make sure i have nothing else running on the computer,
just Logic Pro 9.1.3, so it's not like i'm overloading macbrains.
I have tried all the rebooting, i/o buffer size changing (down to 256), headfones from the mac output/headfones from the soundcard/ etc
but still no luck.
I can record with the low latency button on
and it's kind of better, nearly, but that means i don't get to record with the effects on the channel strip
that affects the recording/playing quite a lot, as i'm used to recording with effects/guitar amps if i go DI.
This was the selling point - that i could record DI wthout disturbing Thee Neighbours.
It seems to have gotten worse recently.
I wonder if it's been corrupted somehow because it also has been acting funny when i bounce down -
the play head is set to 1111 and i save - then in the bounce window
the start position says a silly random number and it takes a few attempts of fiddly changes to get it to stay at 1111...frustration!
Is there something i can do or is this normal? -
it seems weird that a Pro app that cost me so much £s wouldn't work in a simple recording/bounce down set up?
or has anyone else had this problem and fixed it?
If i wipe Logic and install again would i have to go from my Logic Express and then up to my Logic Pro upgrade/extension again?
Any pointers would be greatly appreciated.
Thanks in advance

Hey Fox,
Thanks for that info -well umm, yes i installed the correct drivers.
I use just the AU plugins or the basic logic ones on the channel strip
but even when i was going in dry there was still a delay.
I had experimented with the buffer size, as mentioned, but not gone down that low cus
last time i tried that i had other strange things happen!
But i will try again.
Sample rate was at zero, btw. Always says zero.
But today, when i just opened logic, the sample rate had changed. Strange. I need to understand this side of things so i'm gonna read up.
Also, if plugins are involved, i installed some novation bass station and some freeware TAL bass synth
stuff recently but don't have them up when i'm recording.
Maybe they sit there quietly and interfere just by their facial expressions or sumthing!!
I booted Mr MBP just now and i pulled out the USB and he's shining me a big ole red optical light
out of his output jack!!
In SysPrefs it has only optical digital as an output option.
In the last few days as i was playing around trying to correct the latency issue i noticed that the output options had changed to the UA25 and the 'digital optical' options - rather than the UA25 and 'line out'.
I'm off to go and read up on how to get my line out back, and try this buffer thing again.
Thanks again
Gravity

How to handle latency due Audio/Video live streams.

Hi everybody reading this,
I am using fms3.5 and the scenario that i wish to solve is that:
1) From a flex application client I start publishing a video at x bytes per second.
2) At the receiver's end, I start getting the video very fine at receiver, with Server to client value around x bytes per seconds (almost).
3) But as soon as the bandwidth of the receiver dips down, due to slow net connection, then the receiver is unable to take x bytes per second. Hence at the receiver's end, the server to client value also falls down considerably. and receiver faces latency.
4) While the receiver is facing latency, the publisher continues to flood the receiver with the x bytes per second data.
5) The data starts accumulating in some queue over the server.
6) Now, when the receiver gets its bandwidth back high in some time, suddenly the fms server sends all of the accumulated data to the receiver and it can be seen as an enormous increase in Server to client value towards the receiver.
Please help me for the following problems:
1) Can i keep on flushing/removing the accumulated a/v data, so that a user that is already facing latency must not be further flooded? if possible then how?
2) What is the best way to eradicate latency? Any good alternative so that if people are on a low connection they should not face latency?
Please help.
Regards and Thanks,
Sahil.

You can use NetStreamInfo class , check you documentation of same here : http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/flash/net/NetStreamInfo .html?filter_flex=4.1&filter_flashplayer=10.1&filter_air=2

My Latency is at 1900-2600ms, and, I would like to know if there is any way to fix it or lower it

I have not found any solutions to this, sometimes my Latency can be at 50-80ms, and i don't know why now it is constantly at 2000 ish. It annoys the crap out of me because a simple page on google takes FOREVER to load.
This is the System Info.
Model Name: iMac
Model Identifier: iMac12,1
Processor Name: Intel Core i5
Processor Speed: 2.5 GHz
Number of Processors: 1
Total Number of Cores: 4
L2 Cache (per Core): 256 KB
L3 Cache: 6 MB
Memory: 8 GB
Boot ROM Version: IM121.0047.B1F
SMC Version (system): 1.71f22
Ive gotten a new router in the past, that did nothing, and i am confused because on my tablet, the ping is a normal 70ms, this is why i need help with lowering it on the computer, as you know of you've had similar problems, they are very annoying to deal with. I have no idea what seems to cause this, but something i find interesting, is that when i restart the computer, for about 15 mins after it was restarted, the ping is normal, then it just jumps back up to the 2000's.
I have the latest software OS X Maveriks 10.9.5.
Please help i have been having this problem for a very long time and have never been able to fix it

Please read this whole message before doing anything.
This procedure is a diagnostic test. It’s unlikely to solve your problem. Don’t be disappointed when you find that nothing has changed after you complete it.
The purpose of the test is to determine whether the problem is caused by third-party software that loads automatically at startup or login, by a peripheral device, by a font conflict, or by corruption of the file system or of certain system caches.
Disconnect all wired peripherals except those needed for the test, and remove all aftermarket expansion cards, if applicable. Start up in safe mode and log in to the account with the problem. You must hold down the shift key twice: once when you turn on the computer, and again when you log in.
Note: If FileVault is enabled, or if a firmware password is set, or if the startup volume is a software RAID, you can’t do this. Ask for further instructions.
Safe mode is much slower to start up and run than normal, with limited graphics performance, and some things won’t work at all, including sound output and Wi-Fi on certain models. The next normal startup may also be somewhat slow.
The login screen appears even if you usually login automatically. You must know your login password in order to log in. If you’ve forgotten the password, you will need to reset it before you begin.
Test while in safe mode. Same problem?
After testing, restart as usual (not in safe mode) and verify that you still have the problem. Post the results of the test.

I just want my RAM to run at correct Latency

Well another topic ragarding the problem the Cas Latency
I bought a 2Gb Kit 800 Mhz 4-4-4-12 (TeamGroup)
If i let everything auto as it has been said it defaults to 533
Then I go to Cell Menu and set them at 800 Mhz..Ram Voltage 2.0 V & SPD Auto
The timings are no way near the factory settings
Then as i have seen in other thread u set Cas 4 u get 3....u set Cas 5 u get 5
I was probably one of the few who dared to flash to the latest 1.5b3 but no solution
I know that this issue has being address a lot of times but guess what .... I really Don't Care i just want i have paid for
When i went to see the Product Page of 965 Platinum along with the TomsHardware award i didn't saw any notification that this board has problem with timings and the BIOS cannot handle correctly Ram sticks
I am not asking for something more that is advertised.....hey i am not overclocking so u cannot blame me for something out of specs .... MSI made and advertised a motherboard ..... if it has trouble to do just the basics then i think someone has to pay for this
PS because i have assembled other systems form other brands this strange problem with timings to my knowledge its unique and the ram modules although they are not overclocking monsters they are decent sticks and all the test show that they work to the correct timings even with low than the specs Voltage
As for the specs of my System
CPU : E6600 . Arctic Freezer Pro is handling the task of cooling
M/B The Infamous and the one and only MSI 965 Platinum
RAM: 2 x 1 GB TeamGroup 800 4-4-4-12 (lets see i ever gonna see these timings.... )
PSU : Enermax Liberty 400W
VGA : MSI 7600GT
HDD: 1 Sata Seagate 250 GB . 1 IDE Maxtor 160GB
DVD-RW NEC 4571A (Also known as the Tornado.....just try to play a DVD and u get the point)

I bit sceptic considering the fact that when CAS is set to 4 ->3 the system is unstable.
And to tell the truth it has nothing to do with performance but to me it has to do with proper treatment of customers.
We didn't found this Mobo somewhere in the street,nobody came and said "here you are a nice free motherboard" .
I paid it as probably anyone else and me and my family had to sacrifice something else in order to buy this motherboard and all the other components of my system..... so is it too much to ask a proper BIOS that will take care of problems.
As i have said i am asking for something outside specs i just ask for it should be delivered and considering that this Mobo has being on the market for almost a year i think it is time to stop forgiving an start asking......

Extremely slow and high latency all day.

DSL is running extremely slow during peak hours from 12 afternoon to 12 midnight. Lower than 50% of rated speed and high latency
I have been frustrated with this DSL Service for months now. I am considering contacting BBB to file a complaint and I am tired of dealing with customer service giving me the run around. Internet is a monopoly in my area therefore verizon feels it doesn't have to do anything to keep its customers when they provide crappy service. I am on waitlist for another internet service provider and it is going to take almost a year because of how bad the internet options are in the area and demand for better options. I even had to pay over 100 dollars to get a truck roll come to my house to fix any issues within the house and the internet has not gotten better. Atleast I feel I should get a refund or something.
Here is my speedtest result just now. http://www.speedtest.net/my-result/2899553407
It has been even slower at other times. http://www.speedtest.net/my-result/2893509440
Modem is Westell 6100 or something.
Transceiver Statistics
Transceiver Revision:
7.2.3.0
Vendor ID Code:
4
Line Mode:
G.DMT Mode
Data Path:
Interleaved
Transceiver Information
Downstream Path
Upstream Path
DSL Speed (Kbits/Sec)
3360
864
Margin (dB)
15.5
13.0
Line Attenuation (dB)
21.5
13.0
Transmit Power (dBm)
7.6
11.9
Giganews line info
news.giganews.com
traceroute to {edited for privacy}, 30 hops max, 60 byte packets
1 gw1-g-vlan201.dca.giganews.com (216.196.98.4) 0 ms 0 ms 0 ms
2 ash-bb1-link.telia.net (213.248.70.241) 0 ms 0 ms 0 ms
3 TenGigE0-2-0-0.GW1.IAD8.ALTER.NET (63.125.125.41) 3 ms GigabitEthernet2-0-0.GW8.IAD8.ALTER.NET (63.65.76.189) 3 ms TenGigE0-2-0-0.GW1.IAD8.ALTER.NET (63.125.125.41) 3 ms
4 P1-8-0-0.LSANCA-LCR-21.verizon-gni.net (130.81.151.237) 72 ms 72 ms 72 ms
5 P9-3.LSANCA-LCR-01.verizon-gni.net (130.81.193.123) 75 ms P8-0.LSANCA-DSL-44.verizon-gni.net (130.81.35.133) 75 ms 76 ms
6 * * *
7 * * *
8 * * *
9 * * *
10 * * *
11 * * *
12 * * *
13 * * *
14 * * *
15 * * *
16 * * Max number of unresponsive hops reached (firewall or filter?)
news-europe.giganews.com
traceroute to {edited for privacy}, 30 hops max, 60 byte packets
1 vl201.gw1.ams.giganews.com (216.196.110.3) 0 ms 0 ms 0 ms
2 te7-8.ccr01.ams05.atlas.cogentco.com (149.11.104.17) 0 ms te7-7.ccr01.ams05.atlas.cogentco.com (149.11.104.9) 0 ms te7-8.ccr01.ams05.atlas.cogentco.com (149.11.104.17) 0 ms
3 te0-7-0-16.ccr21.ams03.atlas.cogentco.com (154.54.72.42) 0 ms 0 ms 0 ms
4 te0-3-0-0.ccr21.lon13.atlas.cogentco.com (130.117.48.141) 8 ms 8 ms te0-2-0-0.ccr21.lon13.atlas.cogentco.com (154.54.28.158) 8 ms
5 te0-7-0-4.ccr21.jfk02.atlas.cogentco.com (154.54.84.125) 90 ms te0-0-0-4.ccr21.jfk02.atlas.cogentco.com (154.54.84.129) 90 ms *
6 te0-3-0-6.ccr21.dca01.atlas.cogentco.com (154.54.41.5) 96 ms te0-0-0-2.ccr21.dca01.atlas.cogentco.com (154.54.25.238) 96 ms te0-2-0-7.ccr21.dca01.atlas.cogentco.com (154.54.41.1) 96 ms
7 be2042.ccr21.iad02.atlas.cogentco.com (154.54.26.126) 97 ms 97 ms 97 ms
8 uunet.iad01.atlas.cogentco.com (154.54.13.138) 99 ms verizon.iad01.atlas.cogentco.com (154.54.10.226) 105 ms 105 ms
9 P0-8-0-0.LSANCA-LCR-22.verizon-gni.net (130.81.29.127) 177 ms 178 ms P1-0-0-0.LSANCA-LCR-21.verizon-gni.net (130.81.199.39) 174 ms
10 P8-0.LSANCA-DSL-44.verizon-gni.net (130.81.35.133) 175 ms P9-3.LSANCA-LCR-02.verizon-gni.net (130.81.193.109) 187 ms 182 ms
11 * * *
12 * * *
13 * * *
14 * * *
15 * * *
16 * * *
17 * * *
18 * * *
19 * * *
20 * * *
21 * Max number of unresponsive hops reached (firewall or filter?)
Here is what ICSI Netalyzer Results have stated.
Network Access Link Properties + –
Network performance (?): Latency: 580 ms, Loss: 15.5% –
The round-trip time (RTT) between your computer and our server is 580 ms, which is somewhat high. This may be due to a variety of factors, including distance between your computer and our server, a slow network link, or other network traffic.
We recorded a packet loss of 16%. This loss is very significant and will lead to serious performance problems. It could be due either to very high load on our servers due to a large number of visitors, or problems in your network. Of the packet loss, at least 14.0% of the packets appear to have been lost on the path from your computer to our servers.
TCP connection setup latency (?): 720ms –
The time it takes for your computer to set up a TCP connection with our server is 720 ms, which is quite high. This may be due to a variety of factors, including a significant distance between your computer and our server, a particularly slow or poor network link, or problems in your network.
Background measurement of network health (?): 3 transient outages, longest: 0.8 seconds –
During most of Netalyzr's execution, the client continuously measures the state of the network in the background, looking for short outages. During testing, the client observed 3 such outages. The longest outage lasted for 0.8 seconds. This suggests a general problem with the network where connectivity is intermittent. This loss might also cause some of Netalyzr's other tests to produce incorrect results.
Network bandwidth (?): Upload 700 Kbit/s, Download 2.3 Mbit/s +
Network buffer measurements (?): Uplink 5400 ms, Downlink 1200 ms –
We estimate your uplink as having 5400 ms of buffering. This is quite high, and you may experience substantial disruption to your network performance when performing interactive tasks such as web-surfing while simultaneously conducting large uploads. With such a buffer, real-time applications such as games or audio chat can work quite poorly when conducting large uploads at the same time.
We estimate your downlink as having 1200 ms of buffering. This is quite high, and you may experience substantial disruption to your network performance when performing interactive tasks such as web-surfing while simultaneously conducting large downloads. With such a buffer, real-time applications such as games or audio chat can work quite poorly when conducting large downloads at the same time.
HTTP Tests + –
Address-based HTTP proxy detection (?): OK +
Content-based HTTP proxy detection (?): OK +
HTTP proxy detection via malformed requests (?): OK +
Filetype-based filtering (?): OK +
HTTP caching behavior (?): OK +
JavaScript-based tests (?): OK +
DNS Tests + –
Restricted domain DNS lookup (?): OK +
Unrestricted domain DNS lookup (?): OK +
DNS resolver address (?): OK +
DNS resolver properties (?): Lookup latency 520 ms +
Direct probing of DNS resolvers (?): +
DNS glue policy (?): OK +
DNS resolver port randomization (?): OK +
DNS lookups of popular domains (?): OK +
DNS external proxy (?): OK +
DNS results wildcarding (?): Warning –
Your ISP's DNS server returns IP addresses even for domain names which should not resolve. Instead of an error, the DNS server returns an address of 199.101.28.20, which resolves to search.dnsassist.verizon.net. You can inspect the resulting HTML content here.
There are several possible explanations for this behavior. The most likely cause is that the ISP is attempting to profit from customer's typos by presenting advertisements in response to bad requests, but it could also be due to an error or misconfiguration in the DNS server.
The big problem with this behavior is that it can potentially break any network application which relies on DNS properly returning an error when a name does not exist.
The following lists your DNS server's behavior in more detail.
Please help. I am so frustrated I literally have fights with my family over internet problems. I am right now looking for other options and even starting to think about paying over 100 a month for dedicated line or T1 if they can service my area.

Not a single response from Verizon on this? And after you posted the tests & information they will need? I think I may have to make a service choice soon. Its bad enough Verizon can't post a simple email address for our support, they have removed Usenet access, removed access to our websites (I use HTML so their sitebuilder is useless)... Sheeshe...

Video Latency Issue On The Mac Book Pro 2.4 With Leopard 10.5.5

Gear: Macbook Pro (early 2008 model) - 2.4gigs cpu 2gigs ram - all the latest updates... no other applications running during the test
Hi folks. Currently I am having a latency issue when trying to record directly into iMovie using the built-in microphone and iSight camera. Basically, the video seems 5 - 7 frames late to the audio. I found that a good way to demonstrate this issue was simply doing a few handclaps as a test.
This is a quick handclap test displaying some video latency during recording with the iSight camera in iMovie 08.
- Just download this link — and import it into iMovie 08 - Here is a link to a zip file that you can import into iMovie 08 - It's 2.5meg - .m4v export - Also it was recorded as standard format and audio midi setup app: audio was set to 44.1:
http://www.brainbeast.com/37/clap-1-large.zip
- Play from beginning. As soon as you hear a clap sound — pause with the space bar - then back up before the clap with the left arrows
- Then click the right arrow several times until you hear the beginning of the clap sound ( This is the audio: start frame)
- Now — you will notice the video still has an open hand. At this point click the right arrow, counting as you go several times until you see the hand close. This is the amount of frames that the video is late to the audio. For me it seems to be an average of about 5-7 frames late.
Unfortunately iMovie 06 nor QuickTime will not scrub audio as you go frame by frame with the arrow keys so you cannot test it there. If you have some other application such as final cut Pro, you could test it with that.
! IF YOU WOULD LIKE TO PERFORM THE TEST YOURSELF:
- Just record a new movie in iMovie 08 - using the built-in mic and i-Sight camera — and see if it is also slightly out of sync
Note: to be as fair as possible — I did a slow handclap ( in order to not challenge the frame rates) - also, in order to get the maximum volume I used an open palm ( clap on the palms with your fingers spread out as you can see I did.)
Please let me know if this latency appears to be the same for you as it does for me.
Q: Is it just my machine or does it happen to you too?
Q: Does anyone know a way around this latency issue?
Q: Does anyone know if Apple is aware of this latency issue?

I am experiencing the same incredibly frustrating problem as well. When I record directly into iMovie
'08, the video lags the audio by a fraction of a second.
I have tried shutting down all other applications and having only iMovie up. Same problem.
I tried recording the video into QuickTime instead of iMovie and experienced the same problem. (Which makes me think it is perhaps a hardware or operating system issue.)
I tried the technique suggested here and on other sites of "double-dragging" the clip from the Events pane into a project (one normal drag and one Shift+Cmd drag) so that I had the audio and video as two separate tracks. After muting the audio on the video track, I then attempted to slide the audio over to sync it with the video, but even down at the 1/2 second zoom setting I didn't seem to have enough granularity to move the audio so that it was exactly in sync with the video. I was wishing I could use the arrow keys or something like that to move the audio just one frame at a time.
All I want to do is record a video directly into iMovie '08 - this would seem to be something trivial to do!

I am running on OSX 10.10.1 and have a 2009 imac intel and I am having severe latency issues. I am not familiar with macs as this is my home computer used by other family members. Any help on how to troubleshoot why such latency issues?

I am running on OSX 10.10.1 and have a 2009 imac intel and I am having severe latency issues. I am not familiar with macs as this is my home computer used by other family members. Any help on how to troubleshoot why such latency issues?

When you see a beachball cursor or the slowness is especially bad, note the exact time: hour, minute, second.
These instructions must be carried out as an administrator. If you have only one user account, you are the administrator.
Launch the Console application in any of the following ways:
☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)
☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.
☞ Open LaunchPad and start typing the name.
The title of the Console window should be All Messages. If it isn't, select
          SYSTEM LOG QUERIES ▹ All Messages
from the log list on the left. If you don't see that list, select
          View ▹ Show Log List
from the menu bar at the top of the screen.
Each message in the log begins with the date and time when it was entered. Scroll back to the time you noted above.
Select the messages entered from then until the end of the episode, or until they start to repeat, whichever comes first.
Copy the messages to the Clipboard by pressing the key combination command-C. Paste into a reply to this message by pressing command-V.
The log contains a vast amount of information, almost all of it useless for solving any particular problem. When posting a log extract, be selective. A few dozen lines are almost always more than enough.
Please don't indiscriminately dump thousands of lines from the log into this discussion.
Please don't post screenshots of log messages—post the text.
Some private information, such as your name, may appear in the log. Anonymize before posting.

Why does my 10GB iSCSI setup seem see such high latency and how can I fix it?

I have a iscsi server setup with the following configuration
Dell R510
Perc H700 Raid controller
Windows Server 2012 R2
Intel Ethernet X520 10Gb
12 near line SAS drives
I have tried both Starwind and the built in Server 2012 iscsi software but see similar results. I am currently running the latest version of starwinds free
iscsi server.
I have connected it to a HP 8212 10Gb port which is also connected via 10Gb to our vmware servers. I have a dedicated vlan just for iscsi and have enabled
jumbo frames on the vlan.
I frequently see very high latency on my iscsi storage. So much so that it can timeout or hang vmware. I am not sure why. I can run IOmeter and
get some pretty decent results.
I am trying to determine why I see such high latency 100'ms. It doesn't seem to always happen, but several times throughout the day, vmware is complaining
about the latency of the datastore. I have a 10Gb iscsi connection between the servers. I wouldn't expect the disks to be able to max that out. The highest I could see when running IO meter was around 5Gb. I also don't see much load
at all on the iscsi server when I see the high latency. It seems network related, but I am not sure what settings I could check. The 10Gb connect should be plenty as I said and it is no where near maxing that out.
Any thoughts about any configuration changes I could make to my vmware enviroment, network card settings or any ideas on where I can troubleshoot this. I
am not able to find what is causing it. I reference this document and for changes to my iscsi settings
http://en.community.dell.com/techcenter/extras/m/white_papers/20403565.aspx
Thank you for your time.

I have a iscsi server setup with the following configuration
Dell R510
Perc H700 Raid controller
Windows Server 2012 R2
Intel Ethernet X520 10Gb
12 near line SAS drives
I have tried both Starwind and the built in Server 2012 iscsi software but see similar results. I am currently running the latest version of starwinds free
iscsi server.
I have connected it to a HP 8212 10Gb port which is also connected via 10Gb to our vmware servers. I have a dedicated vlan just for iscsi and have enabled
jumbo frames on the vlan.
I frequently see very high latency on my iscsi storage. So much so that it can timeout or hang vmware. I am not sure why. I can run IOmeter and
get some pretty decent results.
I am trying to determine why I see such high latency 100'ms. It doesn't seem to always happen, but several times throughout the day, vmware is complaining
about the latency of the datastore. I have a 10Gb iscsi connection between the servers. I wouldn't expect the disks to be able to max that out. The highest I could see when running IO meter was around 5Gb. I also don't see much load
at all on the iscsi server when I see the high latency. It seems network related, but I am not sure what settings I could check. The 10Gb connect should be plenty as I said and it is no where near maxing that out.
Any thoughts about any configuration changes I could make to my vmware enviroment, network card settings or any ideas on where I can troubleshoot this. I
am not able to find what is causing it. I reference this document and for changes to my iscsi settings
http://en.community.dell.com/techcenter/extras/m/white_papers/20403565.aspx
Thank you for your time.
If both StarWind and MSFT target show the same numbers I can guess it's network configuration issue. Anything higher then 30 ms is a nightmare :( Did you properly tune your network stacks? What numbers (x-put and latency) you get for raw TCP numbers (NTtcp
and Iperf are handy to show)?
StarWind VSAN [Virtual SAN] clusters Hyper-V without SAS, Fibre Channel, SMB 3.0 or iSCSI, uses Ethernet to mirror internally mounted SATA disks between hosts.

Latency on OC48

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