[OpenAFS-devel] Linux atime nits

[Marc Aurele La France]

On Sun, 17 Jan 2010, Simon Wilkinson wrote:
> On 17 Jan 2010, at 13:48, Marc Aurele La France wrote:

>> Any chance of incorporating these into stable?

> When we last discussed pullups for 1.4.12, we decided that these were
> too high risk for that release (the changes appeared very late in the
> release cycle). MS_NOATIME is sufficiently large that it doesn't appear
> to conflict with any inode flags, up to and including Linus's current
> kernel, so there doesn't appear to be a risk associated with not taking
> them this time round.

Only one more inode flag is needed to create a conflict.  Whether or not 
this occurs before 1.4.13 is released is a risk I gather you are willing 
to take.  I think it's better to be pro-active.

> I'd hope that the MS_NOATIME -> S_NOATIME change will land on the 1.4
> branch immediately after we release 1.4.12, and thus be in 1.4.13. The
> change to the super block flags requires more thought, as the impact is
> potentially far reaching. I'd like to see significantly more testing of
> that change before we commit to it in a stable release.

I can see your point if, and only if, AFS is ever changed to provide 
proper access times.  Otherwise, I don't see how eliminating pointless 
traffic on the wire can create a problem.

On a side note, FWIW, the effectiveness of the MS_NOATIME -> S_NOATIME 
change is dependent on Marc Dionne's 
9b37972e610d38a8f45a027d7c10459e29524088 commit (for >= 2.6.32 kernels, 
that is).

Marc.

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