[OpenAFS] afs.GCPAGs in current releases under Linux (RHEL4/5)

Eric.Hagberg@morganstanley.com Eric.Hagberg@morganstanley.com
Fri, 5 Mar 2010 13:52:21 -0500 (EST)


On Fri, 5 Mar 2010, Simon Wilkinson wrote:

>> One thing I'd noticed in RHEL4 tests (systemtap doesn't seem to give
>> the same result under RHEL5) is that the system time usage
>> corresponds to high frequencies of calling afs_ComputePAGStats.
>> Compiling with AFS_NOSTATS defined or commenting out the section of
>> code in src/afs/afs_user.c that calls afs_ComputePAGStats also
>> relieves the problem.
>
> Just to be clear here, are you seeing a high number of calls to
> afs_ComputePAGStats, or a large amount of system time spent in that
> function?

High number of calls to afs_ComputePAGStats, resulting in system time 
being consumed unreasonably, due to it and corresponding 
text.lock.spinlock system calls.

> I can't see a call to afs_ComputePAGStats in afs_user.c - are you just
> commenting out the body of the function, or is there a call site that
> I am missing?

Sorry, cut-n-paste error. I meant the call to afs_ComputePAGStats in 
src/afs/afs_pioctl.c