OVM 3. network bandwidth fo VMs

Hi,
How network bandwith is allocated accros VMs and how can I change this setup to prioritize VMs ?
I have a single VM Windows 7 + PV drivers running alone on a server and I can only achieve a poor 4,4MB/s, while the underlying server operates at 40MB/s for the same transfert.
Thanks.

Our VM server has 8 gigabit ports...
2 bonded (active/passive) ports for intranet communications.
2 bonded dynamic LAG port for ocfs2 heartbeat on a private 192.168.255.255 network and VLAN
2 bonded dynamic LAG ports for Live migrations and other internal communications on a second private 192.168.255.255 network an VLAN
2 multipathed ports for Iscsi on a third private 192.168.255.255 network and VLAN
As I said the underlying server scp at 40MB/s. Which not very exciting, but fair. There can be read perf issue, write perfs issues. I didn't check the weak link yet.
But the same scp from a VM running (alone) on top of that server is 10 TIMES slower. Tested on both network, intranet or internal OVM private network. ouch.Maybe the problem lies on Windows PV Drivers ?
Edited by: user521138 on Sep 10, 2012 8:59 AM

Similar Messages

Disable "Estimated network bandwidth on one of the connections" check

I have several Windows clients that hang at applying computer settings when starting up. All computers that show this behavior have 2 network adapters. One is the physical adapter another is a virtual adapter created by 3rd party software. Virtual Network
adapter always stays enabled (even if you disable it, it comes right back to the enabled state) and has an APIPA address assigned to it. The OS sees the adapter in connected state and attempts to estimate the network bandwidth on that connection,
but since no traffic is being passed through on this link it's forced to wait for the time out, which causes the delay. So the question is, how do you exclude a specific network adapter from being checked for bandwidth at the OS start
up?
Thanks

Hi,
>>One is the physical adapter another is a virtual adapter created by 3rd party software. Virtual Network adapter always stays enabled (even if you disable it, it comes right back to the enabled state
Based on the description, it's recommended that we contact the vendor support of the software to see if they can help disable the virtual adapter or provide some suggestions regarding the situation.
Best regards,
Frank Shen
Please remember to mark the replies as answers if they help and unmark them if they provide no help. If you have feedback for TechNet Subscriber Support, contact [email protected]

How to calculate network bandwidth for dataguard 11.2

Hi all,
have a customer who needs to setup a new data guard environment in release 11.2.0.2. Primary site will be in Italy, standby site will be in New York.
He would like to know the network bandwidth between primary and standby site needed to obtain the maximum performance in redo transport with or without compression option.
I found a lot of threads and docs indicating some formulas but none of them explained how to:
- calculate network bandwidth on a rac system (having a single instance standby database)
- calculate network bandwidth in case of use redo transport compression
- calculate cpu consumption if using redo transport compression
Could you please give any advice?
A.M.

Hi,
customer made ma a lot of technical question just like the following:
- which are the main factors determining the 30% overhead indicated in the network bandwidth calculation
Required bandwidth = ((Redo rate bytes per sec. / 0.7) * 8) / 1,000,000 = bandwidth in Mbps
- how much bandwidth will I gain if I apply redo transport compression and why redo transport compression and why usually the gzip utility gives me 5X less and oracle compression gives me a maximum of 50-60% of compression even if it uses the same engine of zlib compression as indicated below?
Data Guard redo transport compression uses the same zlib compression engine at level 1 as gzip -1. To estimate the compression ratio you can achieve using Data Guard redo transport compression, first compress an archived redo log file with gzip:
$ gzip -1 <archive redo logfile>.arc
Then use the gzip --list option to explicitly display the compression ratio:
$ gzip --list <archive redo logfile.arc>.gz
Note: Use gzip version 1.3.3 or later. Refer to www.gzip.org for the latest information on gzip.
Could anyone give me any direction?
Thank you
AM

Microsoft Office Outlook 2013 Synchronies, network bandwidth jammed Problem.

I have installed Microsoft Office Outlook 2013 (Standard Edition) in an about 5-6 Laptops, and I am facing issue that while synchronization is going on, my office network bandwidth is being affected. It utilises huge network bandwidth, and because
of that network gets jammed. I have configured using IMAP protocol and using my gmail account in that.
Can any one help me to resolve this issue.
Thanks in advance,
DIPAK AHIR.

Hi,
For your first question : YES network issue happen to all Laptops.
I will explain you the scenario, We are having some where about 80 machines (Including Desktops and Laptops) in our office network, all are working under same internet network. Out of this 80 Users We have 5-6 Laptop users who are using Microsoft
Office Outlook 2013 (Standard Edition). All these 5-6 Laptop Users are having different amount of mails (items) as well as folders. Once any of these user starts his / her mail client - Microsoft Office Outlook 2013, suddenly our network bandwidth gets chocked
and because of which my rest of the 80 users are not getting the Internet access. We have to ask them (Laptop user who has switched ON their Microsoft Office Outlook 2013) to close their mail client, Once Microsoft Office Outlook 2013 has been closed my network
gets stable. At first we thought that it is because of mails are getting downloaded from mail server and hence network is getting jammed, so we did another exercise that let their mails gets downloaded to their local machine and afterwords - next time when
they will start their mail client network should not be affected. But this network jammed scenario is still there, hence I ought to raise this issue.
For your information we have tried removing profile, deleted required folders and reconfigured Microsoft Office Outlook 2013 but still issue is being replicated.
Need your help for the same.
Thanks.
Dipak Ahir.

How to determine network bandwidth for EP 6.0 implementation

Hi
can you please guide me how to determine the network bandwith requirment for SAP EP6.0 implementation for smoother operation
Thanks & Regards
Ashutosh

Hi Ashutosh,
luckily network bandwidth is mostly not a problem as long as it is not very small, e.g. a modem dial-up 56kbps connection on client side. To make sure that the server side outgoing line is strong enough, you'd need to do some math and calculate from the expected request volume how much bandwidth you'd need. Some guidance might be taken out of the how to paper under this link:
https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/com.sap.km.cm.docs/documents/a1-8-4/how to perform sap enterprise portal load testing.zip.
Check chapter 2.4 in the pdf file.
For "smooth operation" you'd need network wise not only worry about bandwidth but also about network latency times and sometimes network quality in regard to % package losses or similar. If your end users are more then 1000 miles away you usualy start seeing response time increases from latency times...
The impacts of networking on performance are many, but so are the tuning possibilities. If you have a lot of end-users accessing EP over a WAN, perhaps even over the Internet, and if they do so over long distance you might want to make EP landscape WAN tuning a dedicated task in your project.
In addition the network requirements of Portal are discussed in this paper : http://service.sap.com/~form/sapnet?_SHORTKEY=01100035870000757275&_SCENARIO=01100035870000000112&_OBJECT=011000358700003943521999E , chapter 3.5.2 Enterprise Portal.
Best Regards, Joerg

The network bandwidth for Background Intelligent Transfer Service (BITS)

I use BITS in Powershell script to download files from Internet. The download speed is 1mb or lower. I tried set 2mb in the following local policy but not working. the reason could be the policy is not for Windows 7. Anyone has suggestion?
Thanks.
Computer Configuration | Administrative Templates | Network | Background Intelligent Transfer Services (BITS) | Limit the maximum network bandwidth for BITS background transfers

Hi，
The following policies are supported in Window 7
Computer Configuration | Administrative Templates | Network | Background Intelligent Transfer Services (BITS) |Set up a maintence schedule to limit the maximum network bandwidth used for BITS Background transfers
or Set up a work schedule to limit the maximum network bandwidth used for BITS Background transfers
see this link
http://blogs.msdn.com/b/wmi/archive/2011/02/02/bits-more-flexible-bandwidth-limit-policies.aspx
And download speed is also related with your network connection, your ISP, setting in your router, your system perfrormance...
Yolanda Zhu
TechNet Community Support

Measure the Network bandwidth usage

Hi,
For application server, is there any Oracle tool to be used to measure the Network bandwidth usage?

Hi，
The following policies are supported in Window 7
Computer Configuration | Administrative Templates | Network | Background Intelligent Transfer Services (BITS) |Set up a maintence schedule to limit the maximum network bandwidth used for BITS Background transfers
or Set up a work schedule to limit the maximum network bandwidth used for BITS Background transfers
see this link
http://blogs.msdn.com/b/wmi/archive/2011/02/02/bits-more-flexible-bandwidth-limit-policies.aspx
And download speed is also related with your network connection, your ISP, setting in your router, your system perfrormance...
Yolanda Zhu
TechNet Community Support

Can not see network bandwidth with either Istat or menumeters

Just got my shiny new MBP 17" I have used both of these utilities in the past and they have options to show me the network bandwidth in the menu bar. Both of them show 0 now. Any suggestions

Go to the Menumeters website: www.ragingmenace.com
There is a beta update version (1.4b4) that addresses this issue with some systems running Snow Leopard.

Java rpc network bandwidth limitation

does anyone knows whats the minumum level of network bandwidth does an rpc require to execute properly?
under 4800 bits/sec we get the following error in the application.
client log is as follows
we get that when we hit the add attachment of a 50 kb file(its transferred around as 15 k after zipping in network ) and 18 seconds after hitting the add button we get the exception.
remote call on the server failz.
i think its coz of low bandwidth rate.it works for 9600 properly.
[2006-02-02 10:56:32,533] AWT-EventQueue-0 org.bsf.remoting.http.HttpSessionClient DEBUG - Start remote call 32 insertEkDokumanCDTO
[2006-02-02 10:56:45,830] AWT-EventQueue-0 org.bsf.remoting.http.HttpSessionClient FATAL - Failure during the http remote call on http://sevr.akbank.com.tr:80/remote/httpSession
java.io.EOFException
     at java.util.zip.GZIPInputStream.readUByte(Unknown Source)
     at java.util.zip.GZIPInputStream.readUShort(Unknown Source)
     at java.util.zip.GZIPInputStream.readHeader(Unknown Source)
     at java.util.zip.GZIPInputStream.<init>(Unknown Source)
     at java.util.zip.GZIPInputStream.<init>(Unknown Source)
     at org.bsf.remoting.http.HttpSessionClient.invokeHttp(HttpSessionClient.java:283)
     at org.bsf.remoting.http.HttpSessionClient.invoke(HttpSessionClient.java:160)
     at org.bsf.remoting.http.HttpServiceInvocationHandler.invoke(HttpServiceInvocationHandler.java:103)
     at $Proxy8.insertEkDokumanCDTO(Unknown Source)
any idea?

failz=fails
rpc is remote procedure call.
i ll talk to programmer tomorrow.
im thinking of time-out too.
personally i have used rpc or socket programs in lan but im not sure
how those act in a slow WAN environment.
thanks for the reply CeciNEstPasUnProgrammeur

What Is The Network Bandwidth Usage Report?

I'm looking at the "Network Bandwidth Usage" report and it's just a list of devices with no bandwidth numbers? Is it ordered by amount of usage and if so, why isn't the usage displayed in the report and how do I see the usage for a device?
This topic first appeared in the Spiceworks Community

Page 22 of this document will give you some numbers that will allow you to estimate the total data used for a meeting. Keep in mind these numbers are what Adobe saw as average consumption, yours may be higher or lower.
http://www.adobe.com/content/dam/Adobe/en/products/adobeconnect/pdfs/web-conferencing/Adob e-Connect-9-Technical-Guide.pdf

Optimize network bandwidth usage in large multi-size corporate environments

SymptomsTo maintain a high protection level, you may notice an increase in bandwidth due to the increased number of updates released per day. Policy Manager Proxy (PMP) installations are especially affected as the additional strain on the likely slower network connection that exists between the remote site hosting the PMP installation(s) and the main corporate site with Policy Manager Server (PMS). The network bandwidth usage can be especially high when computers are turn on on Monday as the update packages accumulate over the weekend.
DiagnosisBy default, the Automatic Update Server (AUS) in PMS calculates byte-level differences for the last five update packages (per update channel). In the event where computers were turned off over the weekend, client machine has missed five updates, and PMS will then download a full update package (Aquarius Windows updates can be approximately 140MB in size). When this happens, network bandwidth usage can be excessively high.
SolutionWe recommend applying the suggested changes on all PMS and PMP systems and all of the F-Secure clients behind PMP installations. This may reduce the update size from 140MB to 10MB. The suggested solution consists of three different changes, outlined below:
1. Increase the number of byte-level difference files stored by the PMS
For Windows
To increase the number of byte-level differentials maintained by Automatic Update Server:
Open [F-Secure Installation Path]\FSAUS.PM\conf\server.cfg in Notepad.
Find the key num_old_versions_to_compare, change the value to 50, and save the file.
Restart Automatic Update Agent (AUA) and Automatic Update Server (AUS). In command prompt: net stop fsaua, net start fsaua, net stop fsms, net start fsms.
For Linux
To increase the number of byte-level differentials maintained by Automatic Update Server:
Open /etc/opt/f-secure/fsaus/conf/server.cfg.
Find the key num_old_versions_to_compare, change the value to 50, and save the file.
Restart Automatic Update Agent (AUA) and Automatic Update Server (AUS) daemons (root privileges required): #/etc/init.d/fspms restart
The overall disk space requirement for PMS increases. We estimate the disk consumption to increase by 10GB. Make sure the hard disk hosting the Policy Manager Server installation (Program files\F-Secure\Management Server 5\) has enough disk space.
2. Increase the cache size available on the PMP for storing files
For Windows
Note: Use the Advanced mode in Policy Manager Console (View >> Advanced mode) to edit the setting.
Go to F-Secure Policy Manager Proxy > Settings > Communication > Cache size.
The default setting is 500. Increase this to 5000 (5GB) and distribute new policies.
Verify the setting on all Policy Manager Proxy systems and adjust the settings, if needed. The setting specifies how much disk space is set aside for storing databases on the Policy Manager Proxy.
For Linux
As Policy Manager Proxy on Linux is not centrally managed, the change involves modifying a configuration file that exists on the Policy Manager Proxy system locally.
Open /etc/opt/f-secure/fspmp/conf/proxy.cfg.
Find the key max_cache_size, and change the value to 5000: max_cache_size=5000.
Restart the fspmp daemon (root privileges required): #/etc/init.d/fspmp restart
3. Adjust the F-Secure Anti-Virus client configuration using Policy Manager Console (PMC) to help prevent clients from immediately falling back to downloading updates directly from the PMS.
In case the client is unable to connect to the Policy Manager Proxy, for example due to high network traffic and multiple downloads taking place, the following setting dictates how soon the client attempts to connect directly to the Policy Manager Server to download updates.
In Policy Manager Console, go to F-secure Automatic Update Agent > Settings > Communications > Policy Manager Proxies > PMP Proxy fallback time.
Default value is zero which means fallback to PMS takes place immediately, in case where Policy Manager Proxy installation cannot be reached. To prevent this from happening, configure this setting to a higher value (suggest 7 hours).
These steps should ensure database updates are only downloaded via the PMP.

SymptomsTo maintain a high protection level, you may notice an increase in bandwidth due to the increased number of updates released per day. Policy Manager Proxy (PMP) installations are especially affected as the additional strain on the likely slower network connection that exists between the remote site hosting the PMP installation(s) and the main corporate site with Policy Manager Server (PMS). The network bandwidth usage can be especially high when computers are turn on on Monday as the update packages accumulate over the weekend.
DiagnosisBy default, the Automatic Update Server (AUS) in PMS calculates byte-level differences for the last five update packages (per update channel). In the event where computers were turned off over the weekend, client machine has missed five updates, and PMS will then download a full update package (Aquarius Windows updates can be approximately 140MB in size). When this happens, network bandwidth usage can be excessively high.
SolutionWe recommend applying the suggested changes on all PMS and PMP systems and all of the F-Secure clients behind PMP installations. This may reduce the update size from 140MB to 10MB. The suggested solution consists of three different changes, outlined below:
1. Increase the number of byte-level difference files stored by the PMS
For Windows
To increase the number of byte-level differentials maintained by Automatic Update Server:
Open [F-Secure Installation Path]\FSAUS.PM\conf\server.cfg in Notepad.
Find the key num_old_versions_to_compare, change the value to 50, and save the file.
Restart Automatic Update Agent (AUA) and Automatic Update Server (AUS). In command prompt: net stop fsaua, net start fsaua, net stop fsms, net start fsms.
For Linux
To increase the number of byte-level differentials maintained by Automatic Update Server:
Open /etc/opt/f-secure/fsaus/conf/server.cfg.
Find the key num_old_versions_to_compare, change the value to 50, and save the file.
Restart Automatic Update Agent (AUA) and Automatic Update Server (AUS) daemons (root privileges required): #/etc/init.d/fspms restart
The overall disk space requirement for PMS increases. We estimate the disk consumption to increase by 10GB. Make sure the hard disk hosting the Policy Manager Server installation (Program files\F-Secure\Management Server 5\) has enough disk space.
2. Increase the cache size available on the PMP for storing files
For Windows
Note: Use the Advanced mode in Policy Manager Console (View >> Advanced mode) to edit the setting.
Go to F-Secure Policy Manager Proxy > Settings > Communication > Cache size.
The default setting is 500. Increase this to 5000 (5GB) and distribute new policies.
Verify the setting on all Policy Manager Proxy systems and adjust the settings, if needed. The setting specifies how much disk space is set aside for storing databases on the Policy Manager Proxy.
For Linux
As Policy Manager Proxy on Linux is not centrally managed, the change involves modifying a configuration file that exists on the Policy Manager Proxy system locally.
Open /etc/opt/f-secure/fspmp/conf/proxy.cfg.
Find the key max_cache_size, and change the value to 5000: max_cache_size=5000.
Restart the fspmp daemon (root privileges required): #/etc/init.d/fspmp restart
3. Adjust the F-Secure Anti-Virus client configuration using Policy Manager Console (PMC) to help prevent clients from immediately falling back to downloading updates directly from the PMS.
In case the client is unable to connect to the Policy Manager Proxy, for example due to high network traffic and multiple downloads taking place, the following setting dictates how soon the client attempts to connect directly to the Policy Manager Server to download updates.
In Policy Manager Console, go to F-secure Automatic Update Agent > Settings > Communications > Policy Manager Proxies > PMP Proxy fallback time.
Default value is zero which means fallback to PMS takes place immediately, in case where Policy Manager Proxy installation cannot be reached. To prevent this from happening, configure this setting to a higher value (suggest 7 hours).
These steps should ensure database updates are only downloaded via the PMP.

Does BC4J need high network bandwidth ?

Hi,
Recently i've done some development with BC4J and test it out against another vendor (BEA,IBM).
Our test scenario is using 5 PC, each running some applications.
for LAN : i run 30 applications in each PC ( 5 PC x 20 applications = 100 Applications Concurrent )
for Modem 64 Kbps : i run 1 applications in each PC ( 5 PC x 1 applications = 5 Applications Concurrent )
Problem:
for LAN the result is fine, but for Modem 64 Kbps i have to increase the concurrent applications since the number of applications is still to small( 5 ),when i monitor the network usage,it seems that my application used all available bandwidth (64Kbps) at apprx.7 concurrent applications.
Questions:
is BC4J need high bandwidth ? or where should i look to tune my applications to use lower bandwidth ?
Thanks in advance,
Ricky HP

Hi Shay,
sorry for late respons..
finally we have finished the POC (Prove Of Concept) session,and comes out with one big question why bc4j require high network bandwidth.
Weblogic team is doing good, they have good performance and good usage of network.But the good news is our client want to use Oracle ADF Framework as their development tools. :)
so here i am, i have to solve about this network bandwidh usage issue.
to answer your question about architecture:
In last POC process,we developed simple client(without gui).
the bc4j components is placed in another linux machine with Oracle 10g Java Edition installed,so the communication between client and bc4j is made through RMI/JNDI,and the communication is made using dial up connection with limited bandwidth network ( 64Kbps modem)
client program is design to loop for several times,to call method in bc4j components.we calculate the time before method is called and after the method is called.
BC4J has good performance but lack in usage network bandwidth.
i've read steve muench tips and tricks for tuning,but seems didn't help a lot in limited network bandwidth environment.
Any help will be appreciated.
Sorry again for late response and thanks a lot
Cheers,
Ricky H.P.
System Analyst / Analyst Programmer
PT.Perkasa Pilar Utama
Jakarta - Indonesia

OVM 3.0.2 - Network Bandwidth with HP Flex-10

Hi All,
In 3.0.2, we can segregate the various network traffic through different network adapters. Using HP's virtual connect Flex-10 hardware, we can carve up a 10 Gb pipe for the different nics.
I would like to find out how you would carve it up given the 5 networks in 3.0.2:
Server Management & Cluster Heartbeat = 0.5 Gb
Live Migration = 1.5 Gb
Virtual Machine = 3 Gb
Storage = 5 Gb
Or would you share the bullk of the pipe like so:
Server Management & Cluster Heartbeat = 0.5 Gb
Live Migration & Virtual Machine & Storage = 9.5 Gb
Given that HP's Flex-10 has no QoS, would this be a good idea to share traffic on the same nic (given the various networks are on seperate vlans)? The 2 Flex-10 modules we have connect to seperate Nexus 5000 switches but I'm still investigating if QoS can be done from the Nexus end.
Thanks.

Hi Avi,
Its mostly to house EBS 12.1.3 virtual machines, 1 app tier and 1 db tier, for each environment like prod, dev, test etc. Very little live migration on a day-to-day basis. Even when taking host offline, I could probably afford to live migrate one vm at a time. So its mainly vm and storage traffic. vm's use virtual disks stored on an nfs repo while each guest hosting an oracle database has a seperate direct nfs mount to its own volume on the NetApp.
We're currently using 2.2.2 with traffic for dom0 (2 bonded nics) and domU (2 bonded nics) without vlans. Looking to move into version 3 of OVM down the road and would like to seperate traffic further using vlans as well. Most documentation I've come across regarding flex-10 is with vmware but the similarities are there with OVM 3.
Problem with flex-10 is carving the bandwidth up isn't exactly very efficient as it can't tap the unused bandwidth if one nic is saturated. While on the other hand, sharing the pipe may have contention issues. Of course my environment probalby doesn't come close to saturating the 10 gb pipe.
But would like to get other views as to how they would desgin their flex-10 environment with OVM 3. Is 0.5 Gb plenty for mgmt & heartbeat? Seperate vm and storage and migration? Or maybe some other configuration? Any ideas thrown up would be most welcome.
Thanks.

Ubd was eating up all network bandwidth after latest upgrade.

Hello,
When the OS X 10.8.2-update (2.0) was installed on my MacBook Air,
Dec 3 20:49:53 MacBookAirPatrick.local installd[914]: Installed "Aanvullende OS X 10.8.2-update" (2.0)
My MacBook Air start to use all my bandwidth.
The reason seems to be the process ubd. I removed this via:
sudo rm -rf /System/Library/PrivateFrameworks/Ubiquity.framework/Versions/A/Support/ubd
What is this process used to and was removing this the right action?
Thanks.

I was given a link to this thread by an AppleCare representative.
I noticed that in the last few days we had been getting through significantly more data than normal - even overnight when the computers are relatively idle it was using about 7 GB.
I was able to log into my Draytek Vigor 2710 router and find out that it was the IP address of my Mac Pro that was using all the data.
Then I used Little Snitch Network Monitor to see what processes were using all the data. As mentioned above it was ubd - and more specifically it was 3 processes - p03-ubiquity.icloud.com, p03-content.icloud.com and another called something like blob. something .windows.net (apparently this is cloud storage used by iCloud).
Concurring with what was said above, I was told it was Documents and Data that seemed to be the problem. I signed out of iCloud and allowed it to delete everything from my Mac Pro, then signed in and restored everything except Documents and Data.
My plan is to see how things go without using iCloud Documents and Data - and if no further problems I'll try ticking that again and monitor it closely.
My suspicion is that some corruption occurred with iCloud documents or the sync process (second problem I've had with iCloud so far).
It's a shame because things like this NEVER seem to happen with Dropbox - even though I use Dropbox far more extensively and for far longer.

Sync iPod with iTunes - reduce network bandwidth for iTunes music folder

I'm using a network drive for my iTunes music folder. Average bandwidth is 50Mbps, compared to, say, an external USB HDD with hi-speed USB bandwidth of 750Mbps.
For some reason iTunes needs to consult the files in the iTunes music folder when syncing an iPod. That is, it needs to access the music files even when there is no change and no files actually need copying from the music folder to the iPod.
Because iTunes is reading my music files, it's really slowing down a sync.
How do I get iTunes only to look at my music folder when there's a file to copy. Reading each file just for a sync is consuming resources and I can't see that it's necessary - iTunes knows what is in my music folder as it has the library xml file stored locally on the PC hosting iTunes.
Anyone have any advice here ?
Thanks.
PS have posted this Q twice before with no replies. Hopefully yet another paraphrase to make the question more relevant with get some help from a kind soul out there.
Here's a link to my previous post(s): http://discussions.apple.com/thread.jspa?threadID=802961

On my Mac, if the external drive with iTunes library is not connected, it will error out and ask if I want to keep looking for the files.
I'm using a network drive for my iTunes music folder. Average bandwidth is 50Mbps
Why so slow? Is it wireless? What kind of connection is it?
iTunes also wants to know if there is a file to delete or if there is a file that has changed.
an external USB HDD with hi-speed USB bandwidth of 750Mbps
USB 2.0 theoretical max speed is 480Mbit/s. Realistic max speed is ~60% of that.
iTunes knows what is in my music folder as it has the library xml file stored locally on the PC hosting iTunes.
iTunes does not use the library.xml file. It is simply created for other applications to access iTUnes library.

OVM 3. network bandwidth fo VMs

Similar Messages

Maybe you are looking for