* Low perfomance of RAID0,RAID5, RAID+LVM on 2.6
@ 2004-08-19 15:32 Vladimir I. Umnov
2004-08-19 15:53 ` David Greaves
2004-08-19 17:26 ` Guy
0 siblings, 2 replies; 5+ messages in thread
From: Vladimir I. Umnov @ 2004-08-19 15:32 UTC (permalink / raw)
To: linux-raid
HW: chipset 875WPE, P4 2.4HT, 3 SATA WD 160JD, 1 ATA Samsung 80Gb.
SW: kernel 2.6.6, libata drivers for PROMISE S150 TX4.
CONFIG: 256K readahead on all drives.
sda1,sdb1,sdc1->RAID0 (md0)
sda2,sdb2,sdc2,hda1->RAID5 (md1)
about 20 partitions on LVM2 with xfs,ext3,reiserfs
chunksize on md0, md1 = 256k - this was optimal with 2.6.0test3 about
year ago.
Theoretically RAID0 read speed should be nearly read speed of one
drive multiply to number of drives, but I have:
dd if=/dev/sda1 of=/dev/null gives about 44 Mb/s on all drives (but on
sii3112 ide driver with WD 160JD about 55Mb/s and on libata the same
44)
>dd if=/dev/md0 of=/dev/null
>2450142720 bytes transferred in 26,436693 seconds (92679622 bytes/sec)
And bus throughput in gkrellm about 180-340 Mb/s
But it's not main problem. Main problem in that LVM2 lower read speed
more than two times:
>dd if=/dev/raid0/video of=/dev/null
>837353472 bytes transferred in 17,210040 seconds (48654941 bytes/sec)
* /dev/raid0/video goes first at md0.
The same results with RAID5(md1):
>kpml:/soft# dd if=/dev/md1 of=/dev/null
>1612713984 bytes transferred in 20,844837 seconds (77367551 bytes/sec)
>kpml:/soft# dd if=/dev/raid5/soft of=/dev/null
>565116928 bytes transferred in 17,450073 seconds (32384789 bytes/sec)
And test results with bonnie++:
kpml:/video# bonnie++ -u 0:0
Using uid:0, gid:0.
Writing with putc()...done
Writing intelligently...done
Rewriting...done
Reading with getc()...done
Reading intelligently...done
start 'em...done...done...done...
Create files in sequential order...done.
Stat files in sequential order...done.
Delete files in sequential order...done.
Create files in random order...done.
Stat files in random order...done.
Delete files in random order...done.
Version 1.03 ------Sequential Output------ --Sequential Input-
--Random- -Per Chr- --Block-- -Rewrite- -Per Chr-
--Block-- --Seeks-- Machine Size K/sec %CP K/sec %CP K/sec %CP
K/sec %CP K/sec %CP /sec %CP kpml 2G 31917 97 99620 19
29519 10 29859 84 59717 12 256.4 1
------Sequential Create------ --------Random Create--------
-Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP
16 4881 32 +++++ +++ 7280 45 4092 31 +++++ +++
3517 25
kpml,2G,31917,97,99620,19,29519,10,29859,84,59717,12,256.4,1,16,4881,32
,+++++,+++,7280,45,4092,31,+++++,+++,3517,25
kpml:/video# cd /soft/
kpml:/soft# bonnie++ -u 0:0
Using uid:0, gid:0.
Writing with putc()...done
Writing intelligently...done
Rewriting...done
Reading with getc()...done
Reading intelligently...done
start 'em...done...done...done...
Create files in sequential order...done.
Stat files in sequential order...done.
Delete files in sequential order...done.
Create files in random order...done.
Stat files in random order...done.
Delete files in random order...done.
Version 1.03 ------Sequential Output------ --Sequential Input-
--Random- -Per Chr- --Block-- -Rewrite- -Per Chr-
--Block-- --Seeks-- Machine Size K/sec %CP K/sec %CP K/sec %CP
K/sec %CP K/sec %CP /sec %CP kpml 2G 31060 97 64993 20
14784 5 18662 52 32736 7 356.7 1
------Sequential Create------ --------Random Create--------
-Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP
16 1199 13 +++++ +++ 857 9 713 7 +++++ +++
560 5
kpml,2G,31060,97,64993,20,14784,5,18662,52,32736,7,356.7,1,16,1199,13,+
++++,+++,857,9,713,7,+++++,+++,560,5
And tiobench:
kpml:/soft# tiobench
No size specified, using 1792 MB
Run #1: /usr/bin/tiotest -t 8 -f 224 -r 500 -b 4096 -d . -TTT
Unit information
================
File size = megabytes
Blk Size = bytes
Rate = megabytes per second
CPU% = percentage of CPU used during the test
Latency = milliseconds
Lat% = percent of requests that took longer than X seconds
CPU Eff = Rate divided by CPU% - throughput per cpu load
Sequential Reads
File Blk Num Avg
Maximum Lat% Lat% CPU Identifier Size
Size Thr Rate (CPU%) Latency Latency >2s >10s
Eff---------------------------- ------ ----- --- ------ ------
--------- ----------- -------- -------- ----- 2.6.6
1792 4096 1 26.81 11.56% 0.142 60.47 0.00000
0.00000 232 2.6.6 1792 4096 2 33.38
16.50% 0.229 76.61 0.00000 0.00000 202 2.6.6
1792 4096 4 37.87 20.62% 0.372 274.79
0.00000 0.00000 184 2.6.6 1792 4096 8
44.65 25.15% 0.602 420.46 0.00000 0.00000 178
Random Reads
File Blk Num Avg
Maximum Lat% Lat% CPU Identifier Size
Size Thr Rate (CPU%) Latency Latency >2s >10s
Eff---------------------------- ------ ----- --- ------ ------
--------- ----------- -------- -------- ----- 2.6.6
1792 4096 1 0.69 0.789% 5.665 54.09 0.00000
0.00000 87 2.6.6 1792 4096 2 1.23
1.452% 6.336 45.20 0.00000 0.00000 84 2.6.6
1792 4096 4 1.65 1.401% 8.882 188.50
0.00000 0.00000 117 2.6.6 1792 4096 8
1.84 1.474% 14.244 291.80 0.00000 0.00000 125
Sequential Writes
File Blk Num Avg
Maximum Lat% Lat% CPU Identifier Size
Size Thr Rate (CPU%) Latency Latency >2s >10s
Eff---------------------------- ------ ----- --- ------ ------
--------- ----------- -------- -------- ----- 2.6.6
1792 4096 1 58.39 34.30% 0.047 189.67 0.00000
0.00000 170 2.6.6 1792 4096 2 56.21
43.01% 0.081 18535.41 0.00044 0.00022 131 2.6.6
1792 4096 4 38.19 32.81% 0.265 33476.28
0.00131 0.00065 116 2.6.6 1792 4096 8
36.54 32.02% 0.464 33756.36 0.00218 0.00131 114
Random Writes
File Blk Num Avg
Maximum Lat% Lat% CPU Identifier Size
Size Thr Rate (CPU%) Latency Latency >2s >10s
Eff---------------------------- ------ ----- --- ------ ------
--------- ----------- -------- -------- ----- 2.6.6
1792 4096 1 0.90 0.580% 0.011 0.77 0.00000
0.00000 155 2.6.6 1792 4096 2 0.85
0.666% 0.014 0.90 0.00000 0.00000 128 2.6.6
1792 4096 4 0.85 0.646% 0.014 0.94
0.00000 0.00000 131 2.6.6 1792 4096 8
0.80 0.627% 0.015 2.74 0.00000 0.00000 127
Seems, that LVM2 is main problem.
I try 2.6.8 and with it md* devices had worse perfomance with all this
tests, on 2.4 perfomance worse than on any 2.6.
What should I do to get read speed greater and have about 20 partitions
on md* block devices? I have a lot of space in LAN to temporarly backup
all data from server and remake something. Additionally I can swap 80Gb
Samsung to 160Gb ATA WD JB.
p.s. Forgive me for bad Eng.
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: Low perfomance of RAID0,RAID5, RAID+LVM on 2.6
2004-08-19 15:32 Low perfomance of RAID0,RAID5, RAID+LVM on 2.6 Vladimir I. Umnov
@ 2004-08-19 15:53 ` David Greaves
2004-08-19 17:26 ` Guy
1 sibling, 0 replies; 5+ messages in thread
From: David Greaves @ 2004-08-19 15:53 UTC (permalink / raw)
To: Vladimir I. Umnov; +Cc: linux-raid
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
Vladimir I. Umnov wrote:
|HW: chipset 875WPE, P4 2.4HT, 3 SATA WD 160JD, 1 ATA Samsung 80Gb.
|SW: kernel 2.6.6, libata drivers for PROMISE S150 TX4.
|CONFIG: 256K readahead on all drives.
| sda1,sdb1,sdc1->RAID0 (md0)
| sda2,sdb2,sdc2,hda1->RAID5 (md1)
| about 20 partitions on LVM2 with xfs,ext3,reiserfs
| chunksize on md0, md1 = 256k - this was optimal with 2.6.0test3 about
| year ago.
|
|Theoretically RAID0 read speed should be nearly read speed of one
|drive multiply to number of drives, but I have:
|dd if=/dev/sda1 of=/dev/null gives about 44 Mb/s on all drives (but on
|sii3112 ide driver with WD 160JD about 55Mb/s and on libata the same
|44)
I use my arrays for large video files so large readahead is good.
I use blockdev on the lvms:
/sbin/blockdev --setra 4096 /dev/video_vg/video_lv
/sbin/blockdev --setra 4096 /dev/video_vg/huge_lv
the md device:
/sbin/blockdev --setra 4096 /dev/md0
and the raw devices
/sbin/blockdev --setra 4096 /dev/sda
/sbin/blockdev --setra 4096 /dev/sdb
/sbin/blockdev --setra 4096 /dev/sdc
/sbin/blockdev --setra 4096 /dev/sdd
/sbin/blockdev --setra 4096 /dev/hdb
HTH
David
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Version: GnuPG v1.2.5 (GNU/Linux)
Comment: Using GnuPG with Thunderbird - http://enigmail.mozdev.org
iD8DBQFBJMz08LvjTle4P1gRAkfpAJ9XA17vexSqmcN0LVFZOx0Dxik/BQCgjMk+
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^ permalink raw reply [flat|nested] 5+ messages in thread
* RE: Low perfomance of RAID0,RAID5, RAID+LVM on 2.6
2004-08-19 15:32 Low perfomance of RAID0,RAID5, RAID+LVM on 2.6 Vladimir I. Umnov
2004-08-19 15:53 ` David Greaves
@ 2004-08-19 17:26 ` Guy
1 sibling, 0 replies; 5+ messages in thread
From: Guy @ 2004-08-19 17:26 UTC (permalink / raw)
To: 'Vladimir I. Umnov', linux-raid
For a single process md only reads from 1 disk at a time.
I think md would use both (or more) disks if the number of processes were
increased. Bit I am not sure about this.
You could try to verify this, but...
By running 2 simple dd commands at the same time would just cause reads from
cache which may double your results, but would not be a valid test.
2 dd commands reading from different sections of the device would avoid the
cache issue but may cause head thrashing. Maybe md tracks where it read
from each device and would use the same disk every time for the same dd
process. I don't know.
Guy
-----Original Message-----
From: linux-raid-owner@vger.kernel.org
[mailto:linux-raid-owner@vger.kernel.org] On Behalf Of Vladimir I. Umnov
Sent: Thursday, August 19, 2004 11:32 AM
To: linux-raid@vger.kernel.org
Subject: Low perfomance of RAID0,RAID5, RAID+LVM on 2.6
HW: chipset 875WPE, P4 2.4HT, 3 SATA WD 160JD, 1 ATA Samsung 80Gb.
SW: kernel 2.6.6, libata drivers for PROMISE S150 TX4.
CONFIG: 256K readahead on all drives.
sda1,sdb1,sdc1->RAID0 (md0)
sda2,sdb2,sdc2,hda1->RAID5 (md1)
about 20 partitions on LVM2 with xfs,ext3,reiserfs
chunksize on md0, md1 = 256k - this was optimal with 2.6.0test3
about
year ago.
Theoretically RAID0 read speed should be nearly read speed of one
drive multiply to number of drives, but I have:
dd if=/dev/sda1 of=/dev/null gives about 44 Mb/s on all drives (but on
sii3112 ide driver with WD 160JD about 55Mb/s and on libata the same
44)
>dd if=/dev/md0 of=/dev/null
>2450142720 bytes transferred in 26,436693 seconds (92679622 bytes/sec)
And bus throughput in gkrellm about 180-340 Mb/s
But it's not main problem. Main problem in that LVM2 lower read speed
more than two times:
>dd if=/dev/raid0/video of=/dev/null
>837353472 bytes transferred in 17,210040 seconds (48654941 bytes/sec)
* /dev/raid0/video goes first at md0.
The same results with RAID5(md1):
>kpml:/soft# dd if=/dev/md1 of=/dev/null
>1612713984 bytes transferred in 20,844837 seconds (77367551 bytes/sec)
>kpml:/soft# dd if=/dev/raid5/soft of=/dev/null
>565116928 bytes transferred in 17,450073 seconds (32384789 bytes/sec)
And test results with bonnie++:
kpml:/video# bonnie++ -u 0:0
Using uid:0, gid:0.
Writing with putc()...done
Writing intelligently...done
Rewriting...done
Reading with getc()...done
Reading intelligently...done
start 'em...done...done...done...
Create files in sequential order...done.
Stat files in sequential order...done.
Delete files in sequential order...done.
Create files in random order...done.
Stat files in random order...done.
Delete files in random order...done.
Version 1.03 ------Sequential Output------ --Sequential Input-
--Random- -Per Chr- --Block-- -Rewrite- -Per Chr-
--Block-- --Seeks-- Machine Size K/sec %CP K/sec %CP K/sec %CP
K/sec %CP K/sec %CP /sec %CP kpml 2G 31917 97 99620 19
29519 10 29859 84 59717 12 256.4 1
------Sequential Create------ --------Random Create--------
-Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP
16 4881 32 +++++ +++ 7280 45 4092 31 +++++ +++
3517 25
kpml,2G,31917,97,99620,19,29519,10,29859,84,59717,12,256.4,1,16,4881,32
,+++++,+++,7280,45,4092,31,+++++,+++,3517,25
kpml:/video# cd /soft/
kpml:/soft# bonnie++ -u 0:0
Using uid:0, gid:0.
Writing with putc()...done
Writing intelligently...done
Rewriting...done
Reading with getc()...done
Reading intelligently...done
start 'em...done...done...done...
Create files in sequential order...done.
Stat files in sequential order...done.
Delete files in sequential order...done.
Create files in random order...done.
Stat files in random order...done.
Delete files in random order...done.
Version 1.03 ------Sequential Output------ --Sequential Input-
--Random- -Per Chr- --Block-- -Rewrite- -Per Chr-
--Block-- --Seeks-- Machine Size K/sec %CP K/sec %CP K/sec %CP
K/sec %CP K/sec %CP /sec %CP kpml 2G 31060 97 64993 20
14784 5 18662 52 32736 7 356.7 1
------Sequential Create------ --------Random Create--------
-Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP
16 1199 13 +++++ +++ 857 9 713 7 +++++ +++
560 5
kpml,2G,31060,97,64993,20,14784,5,18662,52,32736,7,356.7,1,16,1199,13,+
++++,+++,857,9,713,7,+++++,+++,560,5
And tiobench:
kpml:/soft# tiobench
No size specified, using 1792 MB
Run #1: /usr/bin/tiotest -t 8 -f 224 -r 500 -b 4096 -d . -TTT
Unit information
================
File size = megabytes
Blk Size = bytes
Rate = megabytes per second
CPU% = percentage of CPU used during the test
Latency = milliseconds
Lat% = percent of requests that took longer than X seconds
CPU Eff = Rate divided by CPU% - throughput per cpu load
Sequential Reads
File Blk Num Avg
Maximum Lat% Lat% CPU Identifier Size
Size Thr Rate (CPU%) Latency Latency >2s >10s
Eff---------------------------- ------ ----- --- ------ ------
--------- ----------- -------- -------- ----- 2.6.6
1792 4096 1 26.81 11.56% 0.142 60.47 0.00000
0.00000 232 2.6.6 1792 4096 2 33.38
16.50% 0.229 76.61 0.00000 0.00000 202 2.6.6
1792 4096 4 37.87 20.62% 0.372 274.79
0.00000 0.00000 184 2.6.6 1792 4096 8
44.65 25.15% 0.602 420.46 0.00000 0.00000 178
Random Reads
File Blk Num Avg
Maximum Lat% Lat% CPU Identifier Size
Size Thr Rate (CPU%) Latency Latency >2s >10s
Eff---------------------------- ------ ----- --- ------ ------
--------- ----------- -------- -------- ----- 2.6.6
1792 4096 1 0.69 0.789% 5.665 54.09 0.00000
0.00000 87 2.6.6 1792 4096 2 1.23
1.452% 6.336 45.20 0.00000 0.00000 84 2.6.6
1792 4096 4 1.65 1.401% 8.882 188.50
0.00000 0.00000 117 2.6.6 1792 4096 8
1.84 1.474% 14.244 291.80 0.00000 0.00000 125
Sequential Writes
File Blk Num Avg
Maximum Lat% Lat% CPU Identifier Size
Size Thr Rate (CPU%) Latency Latency >2s >10s
Eff---------------------------- ------ ----- --- ------ ------
--------- ----------- -------- -------- ----- 2.6.6
1792 4096 1 58.39 34.30% 0.047 189.67 0.00000
0.00000 170 2.6.6 1792 4096 2 56.21
43.01% 0.081 18535.41 0.00044 0.00022 131 2.6.6
1792 4096 4 38.19 32.81% 0.265 33476.28
0.00131 0.00065 116 2.6.6 1792 4096 8
36.54 32.02% 0.464 33756.36 0.00218 0.00131 114
Random Writes
File Blk Num Avg
Maximum Lat% Lat% CPU Identifier Size
Size Thr Rate (CPU%) Latency Latency >2s >10s
Eff---------------------------- ------ ----- --- ------ ------
--------- ----------- -------- -------- ----- 2.6.6
1792 4096 1 0.90 0.580% 0.011 0.77 0.00000
0.00000 155 2.6.6 1792 4096 2 0.85
0.666% 0.014 0.90 0.00000 0.00000 128 2.6.6
1792 4096 4 0.85 0.646% 0.014 0.94
0.00000 0.00000 131 2.6.6 1792 4096 8
0.80 0.627% 0.015 2.74 0.00000 0.00000 127
Seems, that LVM2 is main problem.
I try 2.6.8 and with it md* devices had worse perfomance with all this
tests, on 2.4 perfomance worse than on any 2.6.
What should I do to get read speed greater and have about 20 partitions
on md* block devices? I have a lot of space in LAN to temporarly backup
all data from server and remake something. Additionally I can swap 80Gb
Samsung to 160Gb ATA WD JB.
p.s. Forgive me for bad Eng.
-
To unsubscribe from this list: send the line "unsubscribe linux-raid" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 5+ messages in thread
* RE: Low perfomance of RAID0,RAID5, RAID+LVM on 2.6
@ 2004-08-19 18:12 Rechenberg, Andrew
2004-08-20 16:11 ` Vladimir I. Umnov
0 siblings, 1 reply; 5+ messages in thread
From: Rechenberg, Andrew @ 2004-08-19 18:12 UTC (permalink / raw)
To: Vladimir I. Umnov; +Cc: linux-raid
Vladimir,
In the part of the message that was quoted to the linux-raid list the
performance of the RAID devices isn't specified. All I see is you
testing /dev/sda1 and mentioning kernel modules, but no mention of
/dev/mdX or /dev/YourVG/YourLV.
What types of numbers are you seeing when using your RAID/LVM devices in
your dd test? Also, you may want to try using bonnie++ to get some
representative numbers as this program tends to be a little more
representative of actual performance without involving the linux VM
cache.
I have yet to use 2.6 for RAID/LVM so I can't point you in a specific
direction, however I didn't see any performance numbers for RAID or LVM
devices.
Try running bonnie++ or /dev/mdX or /dev/YourVG/YourLV and seeing if
it's what you expect.
Good luck,
Andy.
> -----Original Message-----
> From: linux-raid-owner@vger.kernel.org
> [mailto:linux-raid-owner@vger.kernel.org] On Behalf Of David Greaves
> Sent: Thursday, August 19, 2004 11:53 AM
> To: Vladimir I. Umnov
> Cc: linux-raid@vger.kernel.org
> Subject: Re: Low perfomance of RAID0,RAID5, RAID+LVM on 2.6
>
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Vladimir I. Umnov wrote:
>
> |HW: chipset 875WPE, P4 2.4HT, 3 SATA WD 160JD, 1 ATA Samsung 80Gb.
> |SW: kernel 2.6.6, libata drivers for PROMISE S150 TX4.
> |CONFIG: 256K readahead on all drives.
> | sda1,sdb1,sdc1->RAID0 (md0)
> | sda2,sdb2,sdc2,hda1->RAID5 (md1)
> | about 20 partitions on LVM2 with xfs,ext3,reiserfs
> | chunksize on md0, md1 = 256k - this was optimal with
> 2.6.0test3 about
> | year ago.
> |
> |Theoretically RAID0 read speed should be nearly read speed
> of one drive
> |multiply to number of drives, but I have:
> |dd if=/dev/sda1 of=/dev/null gives about 44 Mb/s on all
> drives (but on
> |sii3112 ide driver with WD 160JD about 55Mb/s and on libata the same
> |44)
>
> I use my arrays for large video files so large readahead is good.
>
> I use blockdev on the lvms:
> /sbin/blockdev --setra 4096 /dev/video_vg/video_lv
> /sbin/blockdev --setra 4096 /dev/video_vg/huge_lv
>
> the md device:
> /sbin/blockdev --setra 4096 /dev/md0
>
> and the raw devices
> /sbin/blockdev --setra 4096 /dev/sda
> /sbin/blockdev --setra 4096 /dev/sdb
> /sbin/blockdev --setra 4096 /dev/sdc
> /sbin/blockdev --setra 4096 /dev/sdd
> /sbin/blockdev --setra 4096 /dev/hdb
>
> HTH
>
> David
> -----BEGIN PGP SIGNATURE-----
> Version: GnuPG v1.2.5 (GNU/Linux)
> Comment: Using GnuPG with Thunderbird - http://enigmail.mozdev.org
>
> iD8DBQFBJMz08LvjTle4P1gRAkfpAJ9XA17vexSqmcN0LVFZOx0Dxik/BQCgjMk+
> oAslumzTWosxF9WqnDXln3k=
> =C3uO
> -----END PGP SIGNATURE-----
>
> -
> To unsubscribe from this list: send the line "unsubscribe
> linux-raid" in the body of a message to
> majordomo@vger.kernel.org More majordomo info at
> http://vger.kernel.org/majordomo-info.html
>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: Low perfomance of RAID0,RAID5, RAID+LVM on 2.6
2004-08-19 18:12 Rechenberg, Andrew
@ 2004-08-20 16:11 ` Vladimir I. Umnov
0 siblings, 0 replies; 5+ messages in thread
From: Vladimir I. Umnov @ 2004-08-20 16:11 UTC (permalink / raw)
To: Rechenberg, Andrew, linux-raid
On Thu, 19 Aug 2004 14:12:07 -0400
"Rechenberg, Andrew" <ARechenberg@sfg.com> wrote:
> In the part of the message that was quoted to the linux-raid list the
> performance of the RAID devices isn't specified. All I see is you
> testing /dev/sda1 and mentioning kernel modules, but no mention of
> /dev/mdX or /dev/YourVG/YourLV.
It was my reply to answer, tests with md and lvm was in first message
to this linux-raid lisst.
And setting readahead on lvm volumes helpes. Now I get about 80 Mb/s
read on raid5 and about 100Mb/s on raid0, but the cpu overhead was very
high, but acceptable for me. But it helps only in 2.6.6! 2.6.7 and
2.6.8.1 much slower than 2.6.6.
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2004-08-20 16:11 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
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2004-08-19 15:32 Low perfomance of RAID0,RAID5, RAID+LVM on 2.6 Vladimir I. Umnov
2004-08-19 15:53 ` David Greaves
2004-08-19 17:26 ` Guy
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2004-08-19 18:12 Rechenberg, Andrew
2004-08-20 16:11 ` Vladimir I. Umnov
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