Re: mmap vs fs cache

Jan Kara
2013-03-11T11:52:26Z

On Fri 08-03-13 20:22:19, Phillip Susi wrote:
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> On 03/08/2013 10:00 AM, Howard Chu wrote:
> > Yes, that's what I was thinking. I added a
> > posix_madvise(..POSIX_MADV_RANDOM) but that had no effect on the
> > test.
>
> Yep, that's because it isn't implemented.
Why do you think so? AFAICS it is implemented by setting VM_RAND_READ
flag in the VMA and do_async_mmap_readahead() and do_sync_mmap_readahead()
check for the flag and don't do anything if it is set...

Honza
--
Jan Kara <jack@suse.cz>
SUSE Labs, CR