Andreas Dilger wrote: > On Oct 26, 2007 16:24 -0500, Eric Sandeen wrote: >> The resulting file had over 4k extents. >> [root@bear-05 ~]# filefrag -v /mnt/test/foobar | grep -i extents >> File is stored in extents format >> /mnt/test/foobar: 4075 extents found > > On a related note - we're just putting the finishing touches on the > FIEMAP patches for ext4 + e2fsprogs, so that we can get decent looking > output from filefrag, and much more efficiently than FIBMAP. sounds good. > One of the issues is that w/o delalloc the mballoc code only gets > single-block allocations, so there might be a problem with the interface > to mballoc. That might be caused by the fact the patches were changed > at one point from delalloc-atop-mballoc to mballoc-atop-delalloc, and > something was missed in that conversion. > > Have you tried O_DIRECT? That is another way to access mballoc w/o > using delalloc. I've tried osync: http://people.redhat.com/esandeen/seekwatcher/ext4-dd-osync-write.png but not yet O_DIRECT, will do. -Eric - To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html