Date: Mon, 8 Nov 2004 14:01:39 -0500 From: "Joseph H. Fry" <joe@thefrys.com> To: <freebsd-questions@freebsd.org> Subject: Slow writes using hardware ata raid on older server Message-ID: <002601c4c5c5$61306fd0$f100a8c0@lucy>
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I've finally got a clean updated stable FreeBSD box, thank you all who
have invested your time creating documentation that makes it so easy for
us newbies.
Anyway, I had gentoo on the machine for about 10 minutes... Had a
problem with writing to my Megaraid i4 controller... It was terribly
slow (<1MB/sec)! So I figured I'd try FreeBSD and see how that goes.
I'm no expert, but as far as I can tell Bonnie output (below), things
are not much better.
I only tested with a 100MB file ($ bonnie++ -s 100) because I need to
head to work and didn't want to wait for it to go through a whole 1-2GB
file.
Also below you will find the output from top while bonnie++ was "writing
a byte at a time" and "writing intelligently". I only include these
because I'm not sure how to read them properly for multiple processors.
>From what I can tell, during the byte at a time write the processor is
pegged, but only about 1/4 used during the intelligent write.
Anyway, I'm stuck now with no idea what to do to fix this problem! Any
guidance would be appreciated. (expecially help understanding what the
different values in the bonnie++ output mean)
System:
Dual PII 233 (smp in kernel) on intel server board
128MB ECC SDRAM
LSI MegaRaid i4 ATA RAID Controller (uses amr) in pci slot 1
Onboard Intel e100PRO
3Com 3c595
Adaptec SCSI controller onboard, and one in pci slot
(I don't have the cable I need to connect my CDROM to
the onboard SCSI controller so I added one temporarily)
------Sequential Output------ --Sequential Input- --Random-
-Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP
100M 18 99 2172 8 2105 10 54 99 29052 68 373.4 95
585ms 503ms 613ms 204ms 60668us 3941ms
------Sequential Create------ --------Random Create--------
-Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
Files /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP /sec %CP
16 1204 42 5952 96 5136 99 1024 47 6246 99 4649 88
2547ms 104ms 427us 2682ms 27976us 201ms
1.93c,1.93c,fileserv.thefrys.local,1,1099936265,100M,,18,99,2172,8,2105,
10,54,99,29052,68,373.4,95,16,,,,,1204,42,5952,96,5136,99,1024,47,6246,9
9,4649,88,585ms,503ms,613ms,204ms,60668us,3941ms,2547ms,104ms,427us,2682
ms,27976us,201ms
While writing byte at a
time---------------------------------------------------
last pid: 2317; load averages: 0.81, 0.30, 0.17 up 0+00:54:58
13:49:24
30 processes: 2 running, 27 sleeping, 1 stopped
CPU states: 4.1% user, 0.0% nice, 45.7% system, 0.3% interrupt, 49.8%
idle
Mem: 16M Active, 368K Inact, 27M Wired, 22M Buf, 77M Free
Swap: 510M Total, 100K Used, 510M Free
PID USERNAME PRI NICE SIZE RES STATE C TIME WCPU CPU
COMMAND
2316 jfry 114 0 2380K 1208K CPU1 1 1:37 98.93% 98.19%
bonnie++
2265 jfry 96 0 2380K 1112K STOP 1 0:05 0.00% 0.00%
bonnie++
469 jfry 96 0 6092K 2248K select 0 0:01 0.00% 0.00% sshd
2317 root 96 0 2300K 1368K CPU0 0 0:01 0.00% 0.00% top
2260 jfry 96 0 6092K 2308K select 1 0:00 0.00% 0.00% sshd
2261 jfry 8 0 3092K 1588K wait 0 0:00 0.00% 0.00% bash
379 root 96 0 3440K 2100K select 0 0:00 0.00% 0.00%
sendmail
474 root 20 0 2296K 1600K pause 0 0:00 0.00% 0.00% csh
462 root 4 0 6112K 2152K sbwait 0 0:00 0.00% 0.00% sshd
2257 root 4 0 6112K 2272K sbwait 0 0:00 0.00% 0.00% sshd
.
.
.
While writing
intelligently----------------------------------------------------
last pid: 2321; load averages: 0.59, 0.41, 0.23 up 0+00:56:44
13:51:10
30 processes: 2 running, 27 sleeping, 1 stopped
CPU states: 0.0% user, 0.0% nice, 4.7% system, 0.2% interrupt, 95.2%
idle
Mem: 16M Active, 59M Inact, 36M Wired, 6656K Cache, 22M Buf, 2448K Free
Swap: 510M Total, 100K Used, 510M Free
PID USERNAME PRI NICE SIZE RES STATE C TIME WCPU CPU
COMMAND
2316 jfry 96 0 2380K 1200K CPU1 1 2:48 22.07% 22.07%
bonnie++
2265 jfry 96 0 2380K 1112K STOP 1 0:05 0.00% 0.00%
bonnie++
469 jfry 96 0 6092K 2248K select 1 0:01 0.00% 0.00% sshd
2260 jfry 96 0 6092K 2308K select 1 0:00 0.00% 0.00% sshd
2261 jfry 8 0 3092K 1588K wait 0 0:00 0.00% 0.00% bash
379 root 96 0 3440K 2100K select 1 0:00 0.00% 0.00%
sendmail
474 root 20 0 2296K 1600K pause 1 0:00 0.00% 0.00% csh
462 root 4 0 6112K 2152K sbwait 0 0:00 0.00% 0.00% sshd
2257 root 4 0 6112K 2272K sbwait 0 0:00 0.00% 0.00% sshd
2321 root 96 0 2300K 1352K CPU0 1 0:00 0.00% 0.00% top
.
.
.
Sorry for the long post, I didn't want to leave anything important out.
---- Joe Fry ----
(joe@thefrys.com)
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