Description of problem: Both the 'noac' and 'actimeo=0' mount options should ensure that attributes are not cached, however a bug in nfs_attribute_timeout() means that currently, the attributes may in fact get cached for up to one jiffy. This has been seen to cause corruption in some applications. The reason for the bug is that the time_in_range() test returns 'true' as long as the current time lies between nfsi->read_cache_jiffies and nfsi->read_cache_jiffies + nfsi->attrtimeo. In other words, if jiffies equals nfsi->read_cache_jiffies, then we still cache the attribute data. Version-Release number of selected component (if applicable): 2.6.9-67.EL How reproducible: Dependent on NFS server and workload Steps to Reproduce: 1. have one client host extend a file on an NFS volume 2. have another client host stat & attempt to write into the newly extended area Actual results: The second host does not see the change in file size made by the first immediately despite the use of noac/actimeo=0. Expected results: The change to the size is immediately reflected on all clients. Additional info: Thread/patch from linux-nfs: http://article.gmane.org/gmane.linux.nfs/20074
Created attachment 306286 [details] [PATCH] NFS: Fix nfs_attribute_timeout to ensure it works with actimeo=0 The patch against RHEL-4 is identical. Only the line numbers change in the diff. The attached patch was tested at NetApp, and appears to fix the bug in question. Cheers Trond
I believe this bug is effecting me. Is there any movement from RedHat to integrate this patch?
This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux maintenance release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Update release for currently deployed products. This request is not yet committed for inclusion in an Update release.
Created attachment 308709 [details] Proposed patch
Committed in 78.4.EL . RPMS are available at http://people.redhat.com/vgoyal/rhel4/
Updating PM score.
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-2009-1024.html
The needinfo request[s] on this closed bug have been removed as they have been unresolved for 1000 days