Bug 609020 – subprocess fails in select when descriptors are large

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Bug 609020 - subprocess fails in select when descriptors are large

Summary:	subprocess fails in select when descriptors are large

Status:	CLOSED ERRATA

Aliases:	None

Product:	Red Hat Enterprise Linux 5
Classification:	Red Hat
Component:	python (Show other bugs)
Sub Component:
Version:	5.5
Hardware:	All Linux

Priority	high Severity medium
Target Milestone:	rc
Target Release:	---
Assigned To:	Dave Malcolm
QA Contact:	Petr Šplíchal
Docs Contact:

URL:
Whiteboard:
Keywords:	ZStream

Depends On:
Blocks:	630832 650588
	Show dependency tree / graph

Reported:	2010-06-29 04:25 EDT by Moran Goldboim
Modified:	2018-10-27 09:13 EDT (History)
CC List:	12 users (show)

See Also:
Fixed In Version:
Doc Type:	Bug Fix
Doc Text:	Prior to Python 2.7, programs that used "ulimit -n" to enable communication with large numbers of subprocesses could still monitor only 1024 subprocess file descriptors at a time, which caused an exception: ValueError: filedescriptor out of range in select() This was due to the subprocess module using the "select" system call. The module now uses the "poll" system call, removing this limitation.
Story Points:	---
Clone Of:
Clones:	650588 (view as bug list)
Environment:
Last Closed:	2011-01-13 18:10:14 EST
Type:	---
Regression:	---
Mount Type:	---
Documentation:	---
CRM:
Verified Versions:
Category:	---
oVirt Team:	---
RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---

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External Trackers
Tracker	ID	Priority	Status	Summary	Last Updated
Red Hat Product Errata	RHSA-2011:0027	normal	SHIPPED_LIVE	Low: python security, bug fix, and enhancement update	2011-01-13 05:58:29 EST

Groups: None (edit)

Description Moran Goldboim 2010-06-29 04:25:05 EDT

Description of problem:
since python had a leak (https://bugzilla.redhat.com/show_bug.cgi?id=609017), VDSM was using high filedescriptors, that may be too high for select(). as described in http://bugs.python.org/issue3392

Version-Release number of selected component (if applicable):
python-2.4.3-27.el5

Comment 21 Eva Kopalova 2010-12-20 05:19:39 EST

    Technical note added. If any revisions are required, please edit the "Technical Notes" field
    accordingly. All revisions will be proofread by the Engineering Content Services team.
    
    New Contents:
Prior to Python 2.7, programs that used "ulimit -n" to enable communication with large numbers of subprocesses could still monitor only 1024 file descriptors at a time, which caused an exception:

  ValueError: filedescriptor out of range in select()

This was due to the subprocess module using the "select" system call.  The module now uses the "poll" system call, removing this limitation.

Comment 23 Dave Malcolm 2010-12-20 13:05:56 EST

    Technical note updated. If any revisions are required, please edit the "Technical Notes" field
    accordingly. All revisions will be proofread by the Engineering Content Services team.
    
    Diffed Contents:
@@ -1,4 +1,4 @@
-Prior to Python 2.7, programs that used "ulimit -n" to enable communication with large numbers of subprocesses could still monitor only 1024 file descriptors at a time, which caused an exception:
+Prior to Python 2.7, programs that used "ulimit -n" to enable communication with large numbers of subprocesses could still monitor only 1024 subprocess file descriptors at a time, which caused an exception:
 
   ValueError: filedescriptor out of range in select()

Comment 25 errata-xmlrpc 2011-01-13 18:10:14 EST

An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on therefore solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHSA-2011-0027.html

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