bugGNU Parallel - build and execute command lines from standard input in parallel - Bugs: bug #47565, GNU Parallel incorrectly...

 
 

bug #47565: GNU Parallel incorrectly determines number of CPUs/cores under cygwin

Submitted by:  None
Submitted on:  Tue 29 Mar 2016 03:18:43 PM UTC  
 
Category: NoneSeverity: 3 - Normal
Item Group: NoneStatus: Need Info
Privacy: PublicAssigned to: None
Open/Closed: Closed

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Wed 06 Apr 2016 08:40:53 PM UTC, comment #2:

The screenshot indicates Windows XP. Are we sure the scheduler works for multiple cores?

Please try:

time parallel -j0 "seq 10000000 | bzip2 {} | wc" ::: -9 -9 -9 -9

time parallel -j1 "seq 10000000 | bzip2 {} | wc" ::: -9 -9 -9 -9

If this takes more or less the same time, then I think only one cpu is active even though 4 are shown.

Ole Tange <tange>
Project Administrator
Wed 06 Apr 2016 01:50:54 PM UTC, comment #1:

I have tested on a Cygwin installation, and the output of /proc/cpuinfo is quite different: It has a section for each of the 4 cores and is detected correctly by GNU Parallel. See the attached.

This means that it could be your CygWin installation that is broken.

Can you reproduce your problem on another CygWin installation?

(file #36844)

Anonymous
Tue 29 Mar 2016 03:18:43 PM UTC, original submission:

I am running GNU Parallel (20160222) under Cygwin 2.4.1(0.293/5/3) which is the current version. I have 4 CPUs - screenshot attached.

parallel --number-of-cores return 1 (I expect at least 4)

parallel --number-of-cpus returns 1 (I expect 4)

Diagnostic Output:

perl -e 'print $^O'
cygwin

Anonymous

 

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Attached Files
file #36844:  cpuinfo.txt added by None (3KiB - text/plain)
file #36792:  cpuinfo.txt added by None (588B - text/plain - As already advised to Ole Tange via Email)
file #36793:  Screen Shot 2016-03-22 at 12.11.10.png added by None (235KiB - image/png - As already advised to Ole Tange via Email)

 

Depends on the following items: None found

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    Follow 5 latest changes.

    Date Changed By Updated Field Previous Value => Replaced By
    Wed 20 Apr 2016 09:46:17 PM UTCtangeOpen/ClosedOpen=>Closed
    Wed 06 Apr 2016 08:40:53 PM UTCtangeStatusNone=>Need Info
    Wed 06 Apr 2016 01:50:54 PM UTCNoneAttached File-=>Added cpuinfo.txt, #36844
    Tue 29 Mar 2016 03:18:43 PM UTCNoneAttached File-=>Added cpuinfo.txt, #36792
      Attached File-=>Added Screen Shot 2016-03-22 at 12.11.10.png, #36793

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