> -----Original Message-----
> From: Stewart Smith [mailto:stewart@xxxxxxxxx]
> Sent: Friday, 8 April 2005 12:39 PM
> To: Scott Fagg
> Cc: Steve Lord; linux-xfs@xxxxxxxxxxx
> Subject: RE: database filesystem (ab)use [Was: Re: realtime (
> wasRE:unexpected high fragmentation, any ideas? )]
>
> On Fri, 2005-04-08 at 09:47 +1000, Scott Fagg wrote:
> > Using InnoDB and binary logs gets about 1MB/s throughput on
> the server,
> > but 5MB/s on the desktop.
>
> is dma on? right drivers for the server? sounds like a problem along
> those lines.
I'll look into that.
>
> > I've also tried toggling between mysql v3 and v5, the FC3
> kernel RPM and
> > a vanilla kernel from kernel.org, but all that has had
> little impact.
>
> performance of mysql 3 through 5 should be about the same or better
That's what i've been seeing on the servers that seem to be behaving.
>
> > Other processes can write to disc at much higher rates than
> mysql, so
> > perhaps i should take this problem to a different forum ..
>
> this is interesting... maybe try a bonnie++ run on the disk.
I ran bonnie++ with what seemed like reasonable values and did one run
each, toggling the '-b' option to run with and without fsync();
Good server using XFS (older hardware):
./bonnie++ -d /tmp/ -s 2000 -m bneuxs11 -r 1000 -x 1
bneuxs11,2000M,10349,97,23391,16,13092,13,10242,87,43113,27,482.7,2,16,(
lots of +'s deleted)
./bonnie++ -d /tmp/ -s 2000 -m bneuxs11 -r 1000 -x 1 -b
bneuxs11,2000M,10449,97,20486,14,12483,13,11574,98,43418,27,525.5,3,16,(
lots of +'s deleted)
Mis-behaving Server using ext3fs (new machine):
./bonnie++ -d /tmp/ -s 4000 -m syduxs08 -r 2000 -x 1
syduxs08,4000M,36927,79,43812,14,22258,5,45767,85,61616,5,372.3,0,16,(lo
ts of +'s deleted)
./bonnie++ -d /tmp/ -s 4000 -m syduxs08 -r 2000 -x 1 -b
syduxs08,4000M,39005,84,37419,12,23580,5,50082,92,61995,5,263.4,0,16,(lo
ts of +'s deleted)
I think those results are reasonable, the better machine giving slightly
better numbers.
My insert script produces results like this :
On the good server:
- myisam, no bin-log = 61 seconds, kb/s varied a lot
- myisam, bin-log = 69 seconds, kb/s varied a lot
- innodb, no bin-log = 230 seconds, 3000kb/s
- innodb, bin-log = 230 seconds, 3000kb/s
On the mis-behaving:
- myisam, no bin-log = 24 seconds, 5000kb/s
- myisam, bin-log = 24 seconds, 5000kb/s
- innodb, no bin-log = 24 minutes, 800kb/s
- innodb, bin-log = 24 minutes, 800kb/s
Dud innodb file ?
>
>
> You may also need to tune mysql parameters - check out the
> manual or the
The only tuning i've attempted is to take some hints from the
my-huge.cnf sample file, but that had no discernable impact, possibly
because i'm not really putting much load on the system.
> MySQL Administrator GUI tool (which also does some performance
> monitoring).
>
> --
> Stewart Smith, Software Engineer
> MySQL AB, www.mysql.com
> Office: +14082136540 Ext: 6616
> VoIP: 6616@xxxxxxxxxxxxxxxx
> Mobile: +61 4 3 8844 332
>
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