Alex Kramarov wrote: > > here is a table of messages (34K personalised messages) sent per minute on > different modes : > > ext2 : 417 > ext2 (chattr-S) : 600 > ext3 : 80 > ext3 (chattr-S) data=journal : 430 > ext3 (chattr-S) data=ordered : 370 Interesting, thanks. The way to get high performance with ext3 is to have lots of worker threads, each writing into different directories. This way you get a lot of parallelism and you should get speedups of ten-times or better. But with a single process doing the work, or with all the work happening in the same directory there's not a lot of gain. chattr +S is fairly broken at present - for newly-created files it does a sync for every 4k written. That can easily be changed to a sync-per-write(), which can speed up large-file writes by a factor of up to ten, usually much less. >From the pending-patch-pile: --- linux-2.4.18-pre8/fs/ext3/inode.c Tue Feb 5 00:33:05 2002 +++ linux-akpm/fs/ext3/inode.c Wed Feb 6 23:40:48 2002 @@ -581,8 +581,6 @@ static int ext3_alloc_branch(handle_t *h parent = nr; } - if (IS_SYNC(inode)) - handle->h_sync = 1; } if (n == num) return 0; -
