lvanlys.dll fails to load on PCs with many processors

[blawson]

Just a note so that those who encounter this problem in the future can find it if they search here.

I had an issue with an application failing to start on one computer but not others.  It would raise an error 3: failed to load front panel for a VI in NI_AALBase.lvlib, and then close out.  Windows error reporting showed an application crash caused by lvanlys.dll which was unloaded.

Talked to NI support, it's a known issue under investigation, CAR#287984.

lvanlys.dll fails to load on some high-end machines.  In my case it was a win7 x64 workstation with dual Intel Xeon 8-core hyperthreaded processors, so it has 16 cores and 32 logical processors.  In the other case it was a dual processor Intel Xeon server.  lvanlys loaded successfully for me when I turned off Hyperthreading in the BIOS (so 32 preocessors), and it worked for them when some of the cores were disabled.  To actually fix it I replaced the Analysis VIs with my own in order to eliminate the need to use lvanlys.dll.  This affected me in LV2010 and I assume it is also an issue in 2011 and earlier versions.

Anyway, this was mysterious and frustrating enough that I thought it ought to be searchable.

[Tim_W.]

Hi Barrett,

Thanks for posting this on the forums. I would invite any other community members who have similar issues to please post here or contact NI customer support at www.ni.com/support

Tim W.

Applications Engineering

National Instruments

http://www.ni.com/support  

[D*]

I'm having the same problem on a dual CPU machine with Intel(R) Xeon(R) CPU E5-2687W 0 @ 3.10GHz, 3101 Mhz, 8 Core(s), 16 Logical Processor(s)

Any progress on this? 

[Dominik-E2]

Thank you for posting this information. This issue has definitely been logged in our system and R&D is continuing to investigate the problem. In the meantime, a workaround to this bug is to reduce the maximum number of cores per CPU to 6. Also, every new release of LabVIEW is accompanied with a bug fix list; if this CAR number shows up on that list it would indicate that the problem has been resolved.

[D*]

Is this a problem with the BLAS implementation? If so, does lvanlys.dll call into that package, and would a different BLAS package (http://www.ni.com/white-paper/6205/en) help?

[Dominik-E2]

Unfortunately, I don’t have access to a test machine with the needed specifications to test changing the BLAS package. However, if you would be willing to test this idea I would be interested in seeing the results.

[DSPmchen]

lvanlys.dll calls Intel Math Kernel Library (MKL) package to achieve high performance of some math functions.

The MKL used in LV 2011 and previous version has bug on many core PC. 

This issue will be fixed in next release.

[Mark-Ren]

Have this problem with 2 Xeon CPUs have been solved in LabVIEW 2012 version?

[DSPmchen]

Yes.  This problem has been fixed in LabVIEW 2012.

[Mark-Ren]

I have a computer with  dual CPUs of  Intel(R) Xeon(R) E5-2687W @ 3.10GHz, 8 Core(s), 16 Logical Processor(s). The LabVIEW can run my LabVIEW correctly.

However, with LabVIEW code (with "for" loop parallelism), the CPU usage can only achieve 72% at maximum case for two CPUs. If I switch to one CPU only, the CPU usage can achieve 99%. I compare my computer with two Xeon CPUs with another computer with one i7 2600K CPU (overclock at 4.0 GHz), they have the same speed with the same LabVIEW code !

But I used the CINEBENCH software to test these 2 computers. The computer with 2 Xeon CPUs can achieve 99% CPU usage and the speed is 2.3 times faster than that with one i7 CPU.

So, my conclusion is that that LabVIEW cannot Well support the computer with 2 CPUs.  Is someone else has the same problem?

Thanks.

Deqing Ren.

[Mark-Ren]

I have a computer with  dual CPUs of  Intel(R) Xeon(R) E5-2687W @ 3.10GHz, 8 Core(s), 16 Logical Processor(s). The LabVIEW can run my LabVIEW correctly.

However, with LabVIEW code (with "for" loop parallelism), the CPU usage can only achieve 72% at maximum case for two CPUs. If I switch to one CPU only, the CPU usage can achieve 99%. I compare my computer with two Xeon CPUs with another computer with one i7 2600K CPU (overclock at 4.0 GHz), they have the same speed with the same LabVIEW code !

But I used the CINEBENCH software to test these 2 computers. The computer with 2 Xeon CPUs can achieve 99% CPU usage and the speed is 2.3 times faster than that with one i7 CPU.

So, my conclusion is that that LabVIEW cannot Well support the computer with 2 CPUs.  Is someone else has the same problem?

Thanks.

Deqing Ren.