lkml.org 
[lkml]   [2009]   [May]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    Subject[PATCH] readahead:add blk_run_backing_dev
    Hi.

    I wrote a patch that adds blk_run_backing_dev on page_cache_async_readahead
    so readahead I/O is unpluged to improve throughput.

    Following is the test result with dd.

    #dd if=testdir/testfile of=/dev/null bs=16384

    -2.6.30-rc6
    1048576+0 records in
    1048576+0 records out
    17179869184 bytes (17 GB) copied, 224.182 seconds, 76.6 MB/s

    -2.6.30-rc6-patched
    1048576+0 records in
    1048576+0 records out
    17179869184 bytes (17 GB) copied, 206.465 seconds, 83.2 MB/s

    Sequential read performance on a big file was improved.
    Please merge my patch.

    Thanks.

    Signed-off-by: Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp>

    diff -Nrup linux-2.6.30-rc6.org/mm/readahead.c linux-2.6.30-rc6.unplug/mm/readahead.c
    --- linux-2.6.30-rc6.org/mm/readahead.c 2009-05-18 10:46:15.000000000 +0900
    +++ linux-2.6.30-rc6.unplug/mm/readahead.c 2009-05-18 13:00:42.000000000 +0900
    @@ -490,5 +490,7 @@ page_cache_async_readahead(struct addres

    /* do read-ahead */
    ondemand_readahead(mapping, ra, filp, true, offset, req_size);
    +
    + blk_run_backing_dev(mapping->backing_dev_info, NULL);
    }
    EXPORT_SYMBOL_GPL(page_cache_async_readahead);


    \
     
     \ /
      Last update: 2009-05-18 11:53    [W:0.029 / U:0.036 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site