Re: mmap over nfs leads to excessive system load

From: Kenny Simpson
Date: Wed Nov 16 2005 - 17:03:53 EST

--- Trond Myklebust <trond.myklebust@xxxxxxxxxx> wrote:
> I'm getting lost here. Please could you spell out the testcases that are
> not working.
> Are you saying that the combination mmap() + pwrite64() fails on
> O_DIRECT, but works on ordinary open, and that mmap() + ftruncate64()
> always works?
> Cheers,
> Trond
ftruncate64 works with O_DIRECT
ftruncate64 works w/o O_DIRECT

pwrite64 FAILS with O_DIRECT at ~4GB
pwrite64 works w/o O_DIRECT.

I am re-running these tests to confirm (could take a minute).

All opens are with O_RDWR | O_CREAT | O_LARGEFILE.
All test over GbE w/ jumbo frames (8160 mtu) to a netapp filer (via x-over cable).


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