Xcontrol: performance question (again)

Hello,
I've got a little performance question regarding xcontrols. I observed rather high cpu-load when using xcontrols. To investigate it further, I built a minimal xcontrol (boolean type) which only writes the received boolean-value to a display-element in it's facade (see attached example). When I use this xcontrol in a test-vi and write to it with a rate of 1000 booleans / second, I get a cpu-load of about 10%. When I write directly to a boolean display element instead of the xcontrol,I have a load of 0 to 1 %. The funny thing is, when I emulate the xcontrol functionality with a subvi, a subpanel and a queue (see example), I only have 0 to 1% cpu-load, too.
Is there a way to reduce the cpu-load when using xcontrols?
If there isn't and if this is not a problem with my installation but a known issue, I think this would be a potential point for NI to fix in a future update of LV.
Regards,
soranito
Message Edited by soranito on 04-04-2010 08:16 PM
Message Edited by soranito on 04-04-2010 08:18 PM
Attachments:
XControl_performance_test.zip ‏60 KB

soranito wrote:
Hello,
I've got a little performance question regarding xcontrols. I observed rather high cpu-load when using xcontrols. To investigate it further, I built a minimal xcontrol (boolean type) which only writes the received boolean-value to a display-element in it's facade (see attached example). When I use this xcontrol in a test-vi and write to it with a rate of 1000 booleans / second, I get a cpu-load of about 10%. When I write directly to a boolean display element instead of the xcontrol,I have a load of 0 to 1 %. The funny thing is, when I emulate the xcontrol functionality with a subvi, a subpanel and a queue (see example), I only have 0 to 1% cpu-load, too.
Okay, I think I understand question now. You want to know why an equivalent xcontrol boolean consumes 10x more CPU resource than the LV base package boolean?
Okay, try opening the project I replied yesterday. I don't have access to LV at my desk so let's try this. Open up your xcontrol facade.vi. Notice how I separated up your data event into two events? Go the data change vi event, when looping back the action, set the isDataChanged (part of the data change cluster) to FALSE. While the data input (the one displayed on your facade.vi front panel), set that isDataChanged to TRUE. This is will limit the number of times facade will be looping. It will not drop your CPU down from 10% to 0% but it should drop a little, just enough to give you a short term solution. If that doesn't work, just play around with the loopback statement. I can't remember the exact method.
Yeah, I agree xcontrol shouldn't be overconsuming system resource. I think xcontrol is still in its primitive form and I'm not sure if NI is planning on investing more times to bug fix or even enhance it. Imo, I don't think xcontrol is quite ready for primetime yet. Just too many issues that need improvement.
Message Edited by lavalava on 04-06-2010 03:34 PM

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8) Are some SSDs easier to install / configure / maintain on a MBP than others?
Not that I know of.
9) Are there any issues I should be aware of regarding the installation or use of a SSD that would impact my MBP's warranty?
Just don't break anything doing so, as one is allowed to replace the RAM/storage. However the warranty/AppleCare doesn't cover the newley added items of course.
http://eshop.macsales.com/installvideos/
Based on performance, reliability and 5-year warranty, I've been attracted to the Intel 520. I've also read good reports on the Samsung 830. One review indicated that the 830 maintained performance over time while the 520 experienced a significantly greater drop. True?
Performance isn't going to matter unless your dealing with large amounts of data on a constant basis, a long warranty is always good. But SSD's have no moving parts that I know of, so...easy to give a 5 year warranty. IMO.
Look here
http://www.harddrivebenchmark.net/
I can buy either drive in the $330 range. Here on the forum I've read many recommendations for the OWC drives and support. For comparable performance and a 5-year warranty, it looks like the Extreme Pro would be the model to buy, however, at $460 it is 50% more expensive. Thoughts?
OWC is good, but your basically doing all the work anyway so you can choose to install what you want if you find a faster/larger SSD someplace else.
You need to learn how Lion Recovery Partition works, there are no OS X install disks anymore, it'a all on a partition to boot to install Lion. If you remove the drive, you need to install Lion somehow again right?
Carbon Copy Cloner, clones your entire Lion and Lion Recovery Partition to a external drive, can option boot from it and it's the same thing. Reverse clone onto the new SSD.
Other info you will need.
https://support.apple.com/kb/HT4718
https://support.apple.com/kb/dl1433
http://osxdaily.com/2011/08/08/lion-recovery-disk-assistant-tool-makes-external- lion-boot-recovery-drives/
A option is you can choose is after you installed Windows in Bootcamp (as the machine won't boot a Windows disk from a external optical drive) on the SSD and used WinClone to clone Bootcamp for backup, is to replace the Superdrive with a kit and place the hard drive there for partitioning and storage.
This way the SSD stays unchanged and fast, the hard drive takes all the work of the users files, changes etc, places the wear and tear on that instead.
The Superdrive goes into a enclosure (sold with the kit) and is a external optical drive.
This modification will of course void your warranty/Applecare.
For more information, see Bmer (Dave Merten) over at MacOwnersSupportGroup as he has done this and knows all the tricks.

Controlfile on ASM performance question

Seeing Controlfile Enqueue performance spikes, consideration are to move control file to separater diskgroup(need outage) ? or add some disk(from different luns,( i prefer this approach) in the same disk group , seems like slow disk is casing this issue...
2nd question :can snapshot controlfile be placed on ASM storage?

Following points may help:
- Separating the control file to another diskgroup may make things even worse in case that the total number of disks are insufficient in the new disk group.
- Those control file contention issues are usually nothing to do with the storage throughput you have but the number of operations requiring different levels of exclusion on the control files.
- Since multiple copies of controlfiles are updated concurrently a possible, sometimes, problem is that the secondary copy of controlfile is slower than the other. Please check that this is not the issue (different tiers of storage may cause such problems)
Regards,
Husnu Sensoy

Xcontrol: performance question (again)

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