Re: [PATCH] sort: use posix_fadvise to announce access patterns on files opened for reading

[Erik Auerswald]

Hi,

On Mon, Mar 01, 2010 at 05:33:38PM -0800, Joey Degges wrote:
> Were you sure to remount your devices to clear the cache before running
> these tests? While testing this patch early on the cache caused me many
> incorrect readings. Another approach I took to clear the cache was to fill
> up all of my RAM with some other process.

To clear the caches you can use

echo 3 > /proc/sys/vm/drop_caches

(linux kernel since version 2.6.16).

Erik