Bug 729090

Summary: mmapping a read only file on a gfs2 filesystem incorrectly acquires an exclusive glock
Product: Red Hat Enterprise Linux 5 Reporter: Ken Reilly <kreilly>
Component: kernelAssignee: Phillip Lougher <plougher>
Status: CLOSED ERRATA QA Contact: Red Hat Kernel QE team <kernel-qe>
Severity: high Docs Contact:
Priority: urgent    
Version: 5.6CC: adas, bmarzins, casmith, cww, dhoward, djansa, eguan, jwest, kzhang, mjuricek, pm-eus, qcai, rpeterso, scooter, swhiteho
Target Milestone: rcKeywords: ZStream
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: kernel-2.6.18-238.24.1.el5 Doc Type: Bug Fix
Doc Text:
Performance issues occurred when multiple nodes attempted to call mmap() on the same inode at the same time on a GFS2 file system, as it was using an exclusive glock. With this update, a shared lock is used when "noatime" is set on the mount, allowing mmap() operations to occur in parallel, fixing this bug. Note that this issue only refers to mmap() system calls, and not to subsequent page faults.
Story Points: ---
Clone Of: Environment:
Last Closed: 2011-09-20 17:51:33 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Bug Depends On: 672724    
Bug Blocks:    

Comment 4 Steve Whitehouse 2011-08-08 18:17:24 UTC
Can you confirm the difference between this bug and bug #729088 ?

Comment 5 Steve Whitehouse 2011-08-10 08:33:18 UTC
*** Bug 729088 has been marked as a duplicate of this bug. ***

Comment 7 Phillip Lougher 2011-08-30 16:42:07 UTC
in kernel-2.6.18-238.24.1.el5

linux-2.6-fs-gfs2-no-exclusive-glocks-on-mmapped-read-only-fs.patch

Comment 10 errata-xmlrpc 2011-09-20 17:51:33 UTC
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

http://rhn.redhat.com/errata/RHSA-2011-1321.html

Comment 11 Martin Prpič 2011-09-22 09:19:04 UTC
    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:
Performance issues occurred when multiple nodes attempted to call mmap() on the same inode at the same time on a GFS2 file system, as it was using an exclusive glock. With this update, a shared lock is used when "noatime" is set on the mount, allowing mmap() operations to occur in parallel, fixing this bug. Note that this issue only refers to mmap() system calls, and not to subsequent page faults.