Re: NFS Still broken in 2.6.x?

[Oleg Nesterov]

Andrew morton wrote:
>
> Trond Myklebust <trond.myklebust@xxxxxxxxxx> wrote:
> >
> > On Thu, 2006-02-23 at 15:35 -0500, Bryan Fink wrote:
> >  > Hi All.  I'm running into a bit of trouble with NFS on 2.6.  I see that
> >  > at least Trond thought, mid-January, that "The readahead algorithm has
> >  > been broken in 2.6.x for at least the past 6 months." (
> >  > http://www.ussg.iu.edu/hypermail/linux/kernel/0601.2/0559.html) Anyone
> >  > know if that has been fixed?
> > 
> >  No it hasn't been fixed. ...and no, this is not a problem that only
> >  affects NFS: it just happens to give a more noticeable performance
> >  impact due to the larger latency of NFS over a 100Mbps link.
> 
> iirc, last time we went round this loop Ram and I were unable to reproduce it.
> 
> Does anyone have a testcase?

Afaics, this problem was resolved a long ago.

The patch below should fix this problem. Does it?

Andrew, I'll resend it with a proper changelog and comments on Sunday,
currently I can't even do a compile test. I verified this patch still
applies cleanly.

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