Description of problem: This is a request to backport the upstream kernel 'private futex' functionality to the RHEL5.3 kernel. Use of private futexes will decrease contention on the mmap_sem which is heavily contended in UDP/IP. Upstream Commit: 34f01cc1f512fa783302982776895c73714ebbc2 This is prerequisite for the existing bz 433353 (private futex support in GLIBC)
is the upstream checkin: http://lisa.ines.ro/git/linux-2.6/commit/?id=34f01cc1f512fa783302982776895c73714ebbc2
Raise exception for the RT/Glibc team: Please see bug 433353, comment#9 on why RHEL5 kernel needs to have this feature in in order to support glibc's changes, in term help RT product.
in kernel-2.6.18-115.el5 You can download this test kernel from http://people.redhat.com/dzickus/el5
This bug (feature request) has been marked for inclusion in the Red Hat Enterprise Linux 5.3 Release Notes. To aid in the development of relevant and accurate release notes, please fill out the "Release Notes" field above with the following 4 pieces of information: Cause: What actions or circumstances induced the feature request. Consequence: What action was inhibited by the feature's absence. Fix: What was done to implement the feature. Result: now happens when the actions or circumstances above occur. (NB: this is not the same as 'the feature request was fulfilled')
(In reply to comment #4) > ------- Comment From rlerch 2008-11-04 21:58:58 EDT------- > This bug (feature request) has been marked for inclusion in the Red Hat > Enterprise Linux 5.3 Release Notes. > > To aid in the development of relevant and accurate release notes, please fill > out the "Release Notes" field above with the following 4 pieces of information: > > Cause: What actions or circumstances induced the feature request. > > Consequence: What action was inhibited by the feature's absence. > > Fix: What was done to implement the feature. > > Result: now happens when the actions or circumstances above occur. (NB: this > is not the same as 'the feature request was fulfilled') > The private futex kernel components don't really provide any functional advantages without the user level changes. And, it was my understanding that the glibc changes were rejected for RHEL5.3. Is this correct?
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-2009-0225.html