[lkml]   [2010]   [Oct]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH 15/18] fs: introduce a per-cpu last_ino allocator
On Fri, Oct 08, 2010 at 10:22:34AM +0200, Andi Kleen wrote:
> Dave Chinner <> writes:
> > From: Eric Dumazet <>
> >
> > new_inode() dirties a contended cache line to get increasing
> > inode numbers. This limits performance on workloads that cause
> > significant parallel inode allocation.
> >
> > Solve this problem by using a per_cpu variable fed by the shared
> > last_ino in batches of 1024 allocations. This reduces contention on
> > the shared last_ino, and give same spreading ino numbers than before
> > (i.e. same wraparound after 2^32 allocations).
> This doesn't help for Unix disk file systems, so not fully sure why you
> need it for XFS.

Currently i_ino is assigned for every inode allocated using new_inode.
It's pretty stupid as most callers simply don't need it. But Dave
didn't want to make this series even more complicated than nessecary
and leave sorting this out for later.

 \ /
  Last update: 2010-10-08 10:47    [W:0.150 / U:0.924 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site