Nebojsa Trpkovic <trx.lists@xxxxxxxxx> writes: > On 04/08/10 03:22, Eric Sandeen wrote: >> How does it fail? >> >> Surely a bug. :) If you can provide details we'll look into it. >> (perhaps it's obvious on first try but still worth saying exactly >> what problematic behavior you saw, when reporting a bug you >> encountered) > > Well, I've done a simple test, described like: > > "get the used sectors for a file > hdparm --fibmap filename > read a sector from the file eg. with > sudo hdparm --read-sector 66385920 /dev/sda > delete the file and sync > rm filename;sync > and read the sector a second time" > > > And I get something like this: > > ================================ > # dd if=/dev/urandom of=tempfile count=100 bs=512k oflag=direct > 100+0 records in > 100+0 records out > 52428800 bytes (52 MB) copied, 6.47137 s, 8.1 MB/s > > # hdparm --fibmap tempfile > > tempfile: > filesystem blocksize 4096, begins at LBA 0; assuming 512 byte sectors. > byte_offset begin_LBA end_LBA sectors > 0 37094400 37196799 102400 > > # hdparm --read-sector 37094400 /dev/sdb > > /dev/sdb: > reading sector 37094400: succeeded > b0e8 3ad7 d080 84e8 b4b2 7e60 21f1 eff3 > 0ef9 fa10 b172 89f8 186f 0194 4cb1 e190 > d6b5 b2fe 2577 5dba e6f2 5ad7 34a0 f09f > ca5c 07ef 6e86 c3a8 9e77 77f3 78ff 672f > af71 dea7 ac23 a55d e31e ff83 164e bb76 > 8ea4 416d 343a 9f5e b41f b1d0 b6e9 6ed8 > 90c0 3cba ec07 1d96 fdd6 3940 1290 7cd2 > c506 c3ee c120 3732 17eb 6e68 11aa 721c... > > # rm tempfile > # sync > ================================ > > Now, if I have "data=writeback" enable and I run > # hdparm --read-sector 37094400 /dev/sdb > again, I'll get the same random bytes. > Reboot doesn't help. > > If I disable "data=writeback" and run > # hdparm --read-sector 37094400 /dev/sdb > I'll get all zeroes: > ================================ > # hdparm --read-sector 37094400 /dev/sdb > > /dev/sdb: > reading sector 37094400: succeeded > 0000 0000 0000 0000 0000 0000 0000 0000 > 0000 0000 0000 0000 0000 0000 0000 0000 > 0000 0000 0000 0000 0000 0000 0000 0000 > 0000 0000 0000 0000 0000 0000 0000 0000 > 0000 0000 0000 0000 0000 0000 0000 0000 > 0000 0000 0000 0000 0000 0000 0000 0000 > 0000 0000 0000 0000 0000 0000 0000 0000 > 0000 0000 0000 0000 0000 0000 0000 0000 > ... > ================================ > > So, TRIM command works well, but not with "data=writeback" mount option. > > Other info: > > Intel X25-V 40GB (latest firmware) can you please provide an actual version of firmware. As soon as i know X25 zeroing was disabled. Can you please post an output of your queue flags cat /sys/block/sdXXX/queue/discard_zeroes_data > > Linux box 2.6.33-gentoo #4 SMP Sat Apr 3 05:02:04 CEST 2010 x86_64 > Intel(R) Core(TM) i5 CPU 750 @ 2.67GHz GenuineIntel GNU/Linux > > > Nebojsa > > > -- > 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
