[LU-618] Reads are not included in IO accounting

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.11.0, Lustre 2.10.3
• Affects Version/s: Lustre 1.8.7, Lustre 1.8.6
• Environment: Linux, Lustre b1_8
• Severity: 3
• Bugzilla ID: 24,536
• Assignee: Hongchao Zhang
• Reporter: Mark Hills

Description

Writes are accounted for, but not reads. The supplied patch fixes this.

It seems that the accounting it normally done in the kernels page writeback and readahead
functionality. Therefore as Lustre implements its own readahead, it must also maintain its own
accounting on reads (but not writes).

Previously discussed in:

• http://lists.lustre.org/pipermail/lustre-devel-lustre.org/2011-April/001586.html
• https://bugzilla.lustre.org/show_bug.cgi?id=24536

Issue Links

• Trackbacks: Lustre 1.8.x known issues tracker While testing against Lustre b18 branch, we would hit known bugs which were already reported in Lustre Bugzilla https://bugzilla.lustre.org/. In order to move away from relying on Bugzilla, we would create a JIRA

Comments

[Hongchao Zhang]

the patch has been refreshed

[Andreas Dilger]

This conflict with RHEL5 is probably gone, should the patch be refreshed?

[Hongchao Zhang]

there is a bug in OFED(1.5.3.2) which causes the patch can't be builded successfully in RHEL5, the detailed info is,

for RHEL5, there is no "task_io_account_cancelled_write" definition prior to 2.6.18-164.2.1 and is okay for OFED, which
defines the same function in the backport (in kernel_addons/backport directory), but the function is defined from
2.6.18-164.2.1, then cause the redefinition error when building Lustre with OFED

[Hongchao Zhang]

its patch is tracked at https://review.whamcloud.com/#/c/1636

[Peter Jones]

Hongchao

Please can you take care of porting this patch to master

Thanks

Peter

[Peter Jones]

Mark

Could you please upload the patch into gerrit? There are details on how to do this here - http://wiki.whamcloud.com/display/PUB/Using+Gerrit . If this is not clear enough, please let me know.

Thanks

Peter