Messages in this thread | | | Date | Thu, 31 Jan 2013 15:59:40 -0800 | From | Andrew Morton <> | Subject | Re: [PATCH 2/6] fs: Take mapping lock in generic read paths |
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On Thu, 31 Jan 2013 22:49:50 +0100 Jan Kara <jack@suse.cz> wrote:
> Add mapping lock to struct address_space and grab it in all paths > creating pages in page cache to read data into them. That means buffered > read, readahead, and page fault code.
Boy, this does look expensive in both speed and space.
As you pointed out in [0/n], it's 2-3%. As always with pagecache stuff, the cost of filling the page generally swamps any inefficiencies in preparing that page.
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