On Wed, Dec 18, 2013 at 06:52:44PM +0800, Miao Xie wrote: > In order to improve the performance of fsync, we use the outstanding > ordered extents to avoid looking up the checksum from the csum tree. > But we didn't filter out the ordered extents whose csum is still being > calculated, when we got those ordered extents, we had to wait for the > csum calculation. It made the performance dropped down suddenly. (On > my box, it drop down from 56MB/s to 4-10MB/s) > > But actually, the csum calculation of the ordered extents which were > introduced by the current fsync had already completed. Those ordered > extents whose csum was being calculated didn't belong to the current > fsync, we can ignore them. > > By this patch, the performance fluctuating doesn't happen, and the average > performance grows up by ~2%. > [..] Will this help with apt-get performance over btrfs file system? As far as I understand it it's happening because of multiple fsync calls. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
