Le 22.03.2006 08:41, Hans Reiser a écrit :
> Laurent Riffard wrote:
>
>
>>Hello,
>>
>>Writing big files is very slow on reiser4 now.
>>
>>"dd if=/dev/zero of=toto bs=1k count=102400; sync"
>>
>
> try bs=4M, and tell me what happens. also try an empty fs, and an fs
> that is equally full to reiserfs. Note that reiserfs in your test is
> 68% full vs. 90% full for V4. It may be that we need to port some of
> the block allocation optimizations from V3 to V4 (Jeff's work) to help
> with 90% full filesystems. Thanks for doing this. Real users always
> teach me a lot when they test things differently from how I did.
>
> Hans
Hello Hans,
Yesterday, I realized that my tests were not fair. So I did some
further tests trying to have the same situation for 3 different FS
(reiserfs/ext2/reiser4) and I sent the result to the list, but this
mail never reached the list. I have resent it.
As per your request, I tried to replay my dd test on my 90% full
reiser4 FS, using a 4M block size. Here are the results:
---------------------
> Desktop$ cd ~/kernel
>
> kernel$ rm toto
> rm: détruire fichier régulier `toto'? o
>
> kernel$ df .
> Sys. de fich. Tail. Occ. Disp. %Occ. Monté sur
> /dev/hda8 925M 748M 177M 81% /home/laurent/kernel
>
> kernel$ grep /dev/hda8 /rpoc/mounts
> grep: /rpoc/mounts: Aucun fichier ou répertoire de ce type
>
> kernel$ grep /dev/hda8 /proc/mounts
> /dev/hda8 /home/laurent/kernel reiser4
> rw,nosuid,nodev,atom_max_size=0x7e0c,atom_max_age=0x249f0,atom_min_size=0x100,atom_max_flushers=0x1,cbk_cache_slots=0x10
> 0 0
>
> kernel$ sync; time dd if=/dev/zero of=toto bs=4M count=25; time sync
> 25+0 enregistrements lus.
> 25+0 enregistrements écrits.
> 0.00user 2.89system 0:17.18elapsed 16%CPU (0avgtext+0avgdata 0maxresident)k
> 0inputs+0outputs (0major+252minor)pagefaults 0swaps
> 0.00user 0.00system 2:19.91elapsed 0%CPU (0avgtext+0avgdata 0maxresident)k
> 0inputs+0outputs (0major+191minor)pagefaults 0swaps
>
> kernel$ sync; time dd if=/dev/zero of=toto bs=4M count=25; time sync
> 25+0 enregistrements lus.
> 25+0 enregistrements écrits.
> 0.00user 2.96system 1:16.42elapsed 3%CPU (0avgtext+0avgdata 0maxresident)k
> 0inputs+0outputs (0major+252minor)pagefaults 0swaps
> 0.00user 0.00system 0:08.70elapsed 0%CPU (0avgtext+0avgdata 0maxresident)k
> 0inputs+0outputs (0major+190minor)pagefaults 0swaps
---------------------
I tried to run an "iostat 10" simultaneously with dd+sync. I
attached the output. Hope this helps.
~~
laurent
Le script a débuté sur mer 22 mar 2006 19:12:56 CET
Desktop$ cd ~/kernel
kernel$
kernel$ sleep 15 && echo SYNC && sync && echo DD && time dd if=/dev/zero
of=toto bs=4M count=25 && echo SYNC && time sync && echo END &
[1] 4657
kernel$ iostat -t 10 /dev/hda8
Linux 2.6.16-rc6-mm2 (antares.localdomain) 22.03.2006
Heure: 19:13:32
avg-cpu: %user %nice %system %iowait %idle
5,01 0,02 11,07 4,45 79,46
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
hda8 5,34 0,27 217,58 1297 1026592
Heure: 19:13:42
avg-cpu: %user %nice %system %iowait %idle
0,10 0,00 0,20 0,20 99,50
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
hda8 0,00 0,00 0,00 0 0
SYNC
DD
Heure: 19:13:52
avg-cpu: %user %nice %system %iowait %idle
1,50 0,00 79,32 8,29 10,89
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
hda8 20,38 3,20 1202,00 32 12032
Heure: 19:14:02
avg-cpu: %user %nice %system %iowait %idle
2,30 0,00 81,08 16,62 0,00
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
hda8 33,53 0,00 1398,20 0 13968
Heure: 19:14:12
avg-cpu: %user %nice %system %iowait %idle
1,90 0,00 88,51 9,59 0,00
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
hda8 25,27 0,00 893,51 0 8944
Heure: 19:14:22
avg-cpu: %user %nice %system %iowait %idle
3,19 0,00 85,63 11,18 0,00
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
hda8 27,35 0,00 1288,62 0 12912
Heure: 19:14:32
avg-cpu: %user %nice %system %iowait %idle
0,80 0,00 90,01 9,19 0,00
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
hda8 25,17 0,00 800,00 0 8008
Heure: 19:14:42
avg-cpu: %user %nice %system %iowait %idle
0,30 0,00 74,93 24,78 0,00
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
hda8 54,35 0,00 3138,46 0 31416
Heure: 19:14:52
avg-cpu: %user %nice %system %iowait %idle
0,20 0,00 81,62 18,18 0,00
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
hda8 50,75 0,00 1324,28 0 13256
Heure: 19:15:02
avg-cpu: %user %nice %system %iowait %idle
0,60 0,00 71,60 27,80 0,00
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
hda8 76,30 0,00 2363,20 0 23632
Heure: 19:15:12
avg-cpu: %user %nice %system %iowait %idle
1,10 0,00 29,77 68,93 0,20
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
hda8 123,78 0,00 3275,12 0 32784
25+0 enregistrements lus.
25+0 enregistrements écrits.
0.00user 2.94system 1:29.83elapsed 3%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (0major+252minor)pagefaults 0swaps
SYNC
Heure: 19:15:22
avg-cpu: %user %nice %system %iowait %idle
2,90 0,00 76,60 19,10 1,40
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
hda8 55,10 0,80 1435,20 8 14352
0.00user 0.00system 0:17.41elapsed 0%CPU (0avgtext+0avgdata 0maxresident)k
0inputs+0outputs (0major+190minor)pagefaults 0swaps
END
Heure: 19:15:32
avg-cpu: %user %nice %system %iowait %idle
0,10 0,00 31,73 42,14 26,03
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
hda8 94,19 0,00 3402,60 0 33992
Heure: 19:15:42
avg-cpu: %user %nice %system %iowait %idle
0,10 0,00 0,00 0,10 99,80
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
hda8 0,00 0,00 0,00 0 0
^C
[1]+ Done sleep 15 && echo SYNC && sync && echo DD && time
dd if=/dev/zero of=toto bs=4M count=25 && echo SYNC && time sync && echo END
kernel$ exit
Script complété sur mer 22 mar 2006 19:15:46 CET
