Running tests of fio write with sizes that are less than the write cache size I'm seeing a big slow down when using mmap. I'm running the tests on linux 2.6.31-rc* x86_64. Typical results with default writes :- fio size=300m rw=write write: io=300MiB, bw=314MiB/s, iops=80,418, runt= 955msec with mmap :- fio size=300m rw=write ioengine=mmap write: io=300MiB, bw=55,732KiB/s, iops=13,933, runt= 5512msec Is this expected or is it indicative of a problem somewhere? regards Richard -- To unsubscribe from this list: send the line "unsubscribe fio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
