Re: Inode Lock Scalability V4

Dave Chinner
2010-10-17T02:48:14Z

On Sun, Oct 17, 2010 at 04:55:15AM +1100, Nick Piggin wrote:
> On Sat, Oct 16, 2010 at 07:13:54PM +1100, Dave Chinner wrote:
> > This patch set is just the basic inode_lock breakup patches plus a
> > few more simple changes to the inode code. It stops short of
> > introducing RCU inode freeing because those changes are not
> > completely baked yet.
>
> It also doesn't contain per-zone locking and lrus, or scalability of
> superblock list locking.

Sure - that's all explained in the description of what the series
actually contains later on.

> And while the rcu-walk path walking is not fully baked, it has been
> reviewed by Linus and is in pretty good shape. So I prefer to utilise
> RCU locking here too, seeing as we know it will go in.

I deliberately left out the RCU changes as we know that the version
that is in your tree causes siginificant performance regressions for
single threaded and some parallel workloads on small (<=8p)
machines. There is more development needed there so, IMO, it has
never been a candidate for this series which is aimed directly at
.37 inclusion.

Cheers,

Dave.
--
Dave Chinner
david@fromorbit.com