On 01/31/2012 05:19 AM, Eric Sandeen wrote: > I got nervous when I tried this on an -O bigalloc -C 65536 fs: > > # echo foo > blah; du -hc blah; sync; du -hc blah > 4.0K blah > 4.0K total > 64K blah > 64K total > > Seems that du should never report less than the cluster size, should it? It is a bug and the corresponding fix is sent with the subject "ext4: let getattr report the right blocks in delalloc+bigalloc." > > And that made me wonder about ENOSPC handling - are we tracing delalloc allocations correctly? > > From running xfstest 204 on a similarly-created fs, it really seems that we are not. > > A manual test of creating 4-byte files until ENOSPC (which was really when I ran out of inodes) and then issuing a sync led to a storm of kernel messages about allocation failures: > > [ 482.154538] EXT4-fs (sdb6): delayed block allocation failed for inode 1664 at logical offset 0 with max blocks 1 with error -28 > [ 482.154540] EXT4-fs (sdb6): This should not happen!! Data will be lost > > <ad infinitum, or at least 600 or so in my case> > > and an end result of a bunch of 4 byte long files with no extents. Almost like files full of NULLs. Careful - that is hard to live down. :) yeah, I can reproduce it easily and more investigation is needed here. Thanks Tao > > Ted, are you aware of those issues in bigalloc? > > -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 -- 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
