On 02/07/2012 03:50 AM, Steven Lang wrote: > Similar to the patch last week, this optimizes the pattern verify > operation to use optimized library calls like memcmp(), and only fall > back to byte-by-byte if there is a miscompare to locate it. > > This uses the same premise that the pattern is repeated as many times > as possible to do large compares in a single call. For single byte > pattern, the setup fills the pattern space, and verify assumes it is > full. > > Tested by running a script which created an 8k file with 4k bs and, > one byte at a time, tried corrupting the pattern and running a read > pass and verified it still found miscompares across the whole range of > the pattern. This was done with a pattern length of 1 and 3 bytes. > > In performance tests, this was about 8 times more efficient on > verifies than without this patch. Great, applied! Thanks. -- Jens Axboe -- 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
