Am Montag, 23. Juli 2012 schrieb Marc MERLIN:
> I just realized that the older thread got a bit confusing, so I'll keep
> problems separate and make things simpler :)
>
> On an _unencrypted_ partition on the SSD, running du -sh on a directory
> with 15K files, takes 23 seconds on unencrypted SSD and 4 secs on
> encrypted spinning drive, both with a similar btrfs filesystem, and
> the same kernel (3.4.4).
>
> Unencrypted btrfs on SSD:
> gandalfthegreat:~# mount -o
> compress=lzo,discard,nossd,space_cache,noatime /dev/sda2 /mnt/mnt2
> gandalfthegreat:/mnt/mnt2# echo 3 > /proc/sys/vm/drop_caches; time du
> -sh src 514M src
> real 0m22.667s
>
> Encrypted btrfs on spinning drive of the same src directory:
> gandalfthegreat:/var/local# echo 3 > /proc/sys/vm/drop_caches; time du
> -sh src 514M src
> real 0m3.881s
find is fast, du is much slower:
merkaba:~> echo 3 > /proc/sys/vm/drop_caches ; time ( find /usr | wc -l )
404166
( find /usr | wc -l; ) 0,03s user 0,07s system 1% cpu 9,212 total
merkaba:~> echo 3 > /proc/sys/vm/drop_caches ; time ( du -sh /usr )
11G /usr
( du -sh /usr; ) 1,00s user 19,07s system 41% cpu 48,886 total
Now I try to find something with less files.
merkaba:~> find /usr/share/doc | wc -l
50715
merkaba:~> echo 3 > /proc/sys/vm/drop_caches ; time ( find /usr/share/doc
| wc -l )
50715
( find /usr/share/doc | wc -l; ) 0,00s user 0,02s system 1% cpu 1,398
total
merkaba:~> echo 3 > /proc/sys/vm/drop_caches ; time ( du -sh
/usr/share/doc )
606M /usr/share/doc
( du -sh /usr/share/doc; ) 0,20s user 3,63s system 35% cpu 10,691 total
merkaba:~> echo 3 > /proc/sys/vm/drop_caches ; time du -sh /usr/share/doc
606M /usr/share/doc
du -sh /usr/share/doc 0,19s user 3,54s system 35% cpu 10,386 total
Anyway thats still much faster than your measurements.
merkaba:~> df -hT /usr
Dateisystem Typ Größe Benutzt Verf. Verw% Eingehängt auf
/dev/dm-0 btrfs 19G 11G 5,6G 67% /
merkaba:~> btrfs fi sh
failed to read /dev/sr0
Label: 'debian' uuid: […]
Total devices 1 FS bytes used 10.25GB
devid 1 size 18.62GB used 18.62GB path /dev/dm-0
Btrfs Btrfs v0.19
merkaba:~> btrfs fi df /
Data: total=15.10GB, used=9.59GB
System, DUP: total=8.00MB, used=4.00KB
System: total=4.00MB, used=0.00
Metadata, DUP: total=1.75GB, used=670.43MB
Metadata: total=8.00MB, used=0.00
merkaba:~> grep btrfs /proc/mounts
/dev/dm-0 / btrfs rw,noatime,compress=lzo,ssd,space_cache,inode_cache 0 0
Somewhat aged BTRFS filesystem on ThinkPad T520, Intel SSD 320, kernel
3.5.
Ciao,
--
Martin 'Helios' Steigerwald - http://www.Lichtvoll.de
GPG: 03B0 0D6C 0040 0710 4AFA B82F 991B EAAC A599 84C7
--
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
