• A
    block: Added in stricter no merge semantics for block I/O · 488991e2
    Alan D. Brunelle 提交于
    Updated 'nomerges' tunable to accept a value of '2' - indicating that _no_
    merges at all are to be attempted (not even the simple one-hit cache).
    
    The following table illustrates the additional benefit - 5 minute runs of
    a random I/O load were applied to a dozen devices on a 16-way x86_64 system.
    
    nomerges        Throughput      %System         Improvement (tput / %sys)
    --------        ------------    -----------     -------------------------
    0               12.45 MB/sec    0.669365609
    1               12.50 MB/sec    0.641519199     0.40% / 2.71%
    2               12.52 MB/sec    0.639849750     0.56% / 2.96%
    Signed-off-by: NAlan D. Brunelle <alan.brunelle@hp.com>
    Signed-off-by: NJens Axboe <jens.axboe@oracle.com>
    488991e2
sysfs-block 5.2 KB