Bug 149502
Summary: | performance drop in SMP | ||||||||||
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Product: | Red Hat Enterprise Linux 4 | Reporter: | Dmitri A. Sergatskov <dasergatskov> | ||||||||
Component: | kernel | Assignee: | Steve Dickson <steved> | ||||||||
Status: | CLOSED CURRENTRELEASE | QA Contact: | Brian Brock <bbrock> | ||||||||
Severity: | medium | Docs Contact: | |||||||||
Priority: | medium | ||||||||||
Version: | 4.0 | CC: | davej, dshaks, k.georgiou, mingo, riel | ||||||||
Target Milestone: | --- | ||||||||||
Target Release: | --- | ||||||||||
Hardware: | i386 | ||||||||||
OS: | Linux | ||||||||||
Whiteboard: | |||||||||||
Fixed In Version: | RHSA-2006:0132 | Doc Type: | Bug Fix | ||||||||
Doc Text: | Story Points: | --- | |||||||||
Clone Of: | Environment: | ||||||||||
Last Closed: | 2006-07-14 19:43:42 UTC | Type: | --- | ||||||||
Regression: | --- | Mount Type: | --- | ||||||||
Documentation: | --- | CRM: | |||||||||
Verified Versions: | Category: | --- | |||||||||
oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |||||||||
Cloudforms Team: | --- | Target Upstream Version: | |||||||||
Embargoed: | |||||||||||
Attachments: |
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Description
Dmitri A. Sergatskov
2005-02-23 17:42:09 UTC
Created attachment 111441 [details]
plot of times vs size for SMP and UP
Times transposure of matrix DxD size as a
function of size. Compare SMP and UP modes.
I did some additional testing. The figure ftp://coffee.phys.unm.edu/pub/dima/octave/cpuscale.png shows times obtained in SMP mode and in uni-processor (UP) mode on the same hardware (2xAthlon 2000MHz / 1 GB RAM). The swap was turned off for the test. One can see a curious region around D=2000 to 4000 when UP outperform SMP by almost a factor of 3. The reason for deviation from O(d^2) law at high D is not clear to me either. Created attachment 120499 [details]
NFS locking fixes that release the kernel_lock in do_unlk()
Ingo, this cause of this appears to be the missing unlock_kernel() in
do_unlk(). Its part of the NFS locking changes targeted for RHEL4-U3.
Larry Woodman
Created attachment 120512 [details]
The correct patch
Note patch that Larry posted does not the needed the fix
in it and also breaks lock tests (i.e. F_TEST) by passing
back the wrong value when a lock does not exist.
Please try the one I just attached.
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