Messages in this thread |  | | | Date | Mon, 26 May 2008 16:20:10 +0900 | | From | Hisashi Hifumi <> | | Subject | Re: [PATCH] VFS: Pagecache usage optimization on pagesize !=blocksize environment | |
> But I'm slightly confused that the patch helps because I've always
>thought that mpage_readpage() (which is what we end up calling from
>do_generic_mapping_read()) always reads the whole page. Thus either all
>buffers in the page or none of them are uptodate... So what do I miss
>here?
>
> Honza
On ext3/4, a file is written through buffer/block. So if a page has multiple
buffers, buffers can be uptodate partially especially under random write workloads.
See __block_prepare_write and __block_commit_write.
|  |