On Mon, Aug 23, 2010 at 10:47:55AM -0400, Chris Mason wrote: > The aio batching code is using igrab to get an extra reference on the > inode so it can safely batch. igrab will go ahead and take the global > inode spinlock, which can be a bottleneck on large machines doing lots > of AIO. > > In this case, igrab isn't required because we already have a reference > on the file handle. It is safe to just bump the i_count directly > on the inode. > > Benchmarking shows this patch brings IOP/s on tons of flash up by about > 2.5X. There's some places in XFS where we do the same, and it showed up as a bottle neck before. Instead of open coding the increment we have a wrapper that includes and assert that the numbers is always positive. I think we really want a proper helper for general use instead of completly opencoding it. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
