Re: VFS scalability

Nick Piggin
2005-06-27T08:03:19Z

Andi Kleen wrote:
> On Mon, Jun 27, 2005 at 05:33:43PM +1000, Nick Piggin wrote:
>
>>>Maybe adding a prefetch for it at the beginning of sys_read()
>>>might help, but then with 64CPUs writing to parts of the inode
>>>it will always thrash no matter how many prefetches.
>>>
>>
>>True. I'm just not sure what is causing the bouncing - I guess
>>->f_count due to get_file()?
>
>
> That's in the file, not in the inode. It must be some inode field.
> I don't know which one.
>

Oh yes, my mistake.

> There is probably some oprofile/perfmon event that could tell
> you which function dirties the cacheline.
>

I'll see if I can work it out. Thanks.

--
SUSE Labs, Novell Inc.

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