Re: Lockless page cache test results

From: Nick Piggin
Date: Thu Apr 27 2006 - 11:17:09 EST


Jens Axboe wrote:
On Thu, Apr 27 2006, Nick Piggin wrote:

Hmm, what's more, find_get_pages_contig shouldn't result in any
fewer tree_lock acquires than the open coded thing there now
(for the densely populated pagecache case).


How do you figure? The open coded one does a find_get_page() on each
page in that range, so for x number of pages we'll grab and release
->tree_lock x times.

Yeah you're right. I had in mind that you were using
find_get_pages_contig in readahead, rather than in splice.

--
SUSE Labs, Novell Inc.
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