Re: Tsearch2 Initial Search Speed

On Tue, 17 Jun 2008, Alan Hodgson wrote:
> On Tuesday 17 June 2008, Howard Cole <howardnews(at)selestial(dot)com> wrote:
>> Incidentally, how can I clear the cache in between queries?
>
> Stop PostgreSQL, unmount the filesystem it's on, remount it, restart
> PostgreSQL. Works under Linux.
>
> If it's on a filesystem you can't unmount hot, you'll need to reboot.

Not true - on recent Linux kernels, you can drop the OS cache by running

echo "1" >/proc/sys/vm/drop_caches

as root. You'll still need to restart Postgres to drop its cache too.

Matthew

--
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2. If you must buy a computer, don't turn it on.