Poor parallelization performance on Xeon (E5 v4) Workstation


Jan 7, 2004
Question: At work we recently built a workstation (2x E5-2683v4, 128GB kingston ecc RAM quad-channel, Intel DBS2600CW2R motherboard). Hyperthreading is disabled for the particular application that we are running, as HT is known to cause poor performance for this app. OS is Win7 x64 Enterprise.

We are seeing poor parallelization beyond 16 cores (e.g. once we jump from physical CPU #1 to physical CPU #2). It feels like there's probably a BIOS setting or something that needs to be tweaked.

Anyone have any thoughts? I'd be happy to supply additional info if needed. Thanks!

edit: I think we may have figured out the problem. It turns out that we needed to run a larger 'case study' with our application to see the scaling effect we were expecting (e.g. our initial 'case' was too small to see good parallelization). Thanks to everybody who took a look - sorry to waste your time.
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Another thing you might want to try is enable ht and only use one CPU. Many multiple CPU rigs suffer a performance loss runing on multiple CPUs.