Re: Proposal: Use hi-res clock for file timestamps

J. Bruce Fields
2010-08-18T18:57:11Z

On Wed, Aug 18, 2010 at 07:50:40PM +0200, Andi Kleen wrote:
> > - nfsd updates it whenever it reads an mtime out of an inode that matches
> > current_fs_time to the granularity of 1/HZ.
>
> That means you have a very very hot cache line on a larger system
> if there are a lot of mtime changes. Probably a bad idea.

Only if those mtime changes are also followed immediately by nfsd reads
of the mtime.

That will be the typical case for nfsd writes, though.

--b.