Re: Kernel 2.6.15.1 + NFS is 4 times slower than FTP!?

[Justin Piszcz]

Writing from SRC(A) -> DST(B).
I have not tested reading, but as I recall there were similar speed issues 
going the other way too, although I have not tested it recently.

Justin.

On Tue, 17 Jan 2006, Trond Myklebust wrote:

> On Tue, 2006-01-17 at 13:24 -0500, Justin Piszcz wrote:
> > Alan, is it normal for FTP to be 2x as fast as NFS?
> > With 100mbps, I never seemed to have any issues, but with GIGABIT I
> > definitely see all sorts of weird issues.
>
> Reading or writing?
>
> The readahead algorithm has been borken in 2.6.x for at least the past 6
> months. It leads to NFS collapsing down to 4k reads on the wire instead
> of doing 32k or 64k.
> An effort was made to look at fixing this, but it turns out that nobody
> really understands the current messy implementation, and so progress has
> been slow.
>
> Cheers,
>  Trond
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