Re: Very low disk performance Highpoint 1820a
From: Eric Anderson (anderson_at_centtech.com)
Date: 04/28/05
- Previous message: Steven Hartland: "Re: Very low disk performance Highpoint 1820a"
- Maybe in reply to: Steven Hartland: "Re: Very low disk performance Highpoint 1820a"
- Next in thread: Steven Hartland: "Re: Very low disk performance Highpoint 1820a"
- Reply: Steven Hartland: "Re: Very low disk performance Highpoint 1820a"
- Reply: Arne : "Re: Very low disk performance Highpoint 1820a"
- Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
Date: Thu, 28 Apr 2005 09:42:16 -0500 To: Steven Hartland <killing@multiplay.co.uk>
Steven Hartland wrote:
> I've just finished putting together a new server box spec:
> Dual AMD 244, 2GB ram, 5 * Seagate SATA 400GB on a
> Highpoint 1820a RAID 5 array.
> The machine is currently running 5.4-STABLE ( from the
> weekend ) After install I did some basic tests and the
> disk is return very poor performance low in fact than a
> single disk on a bog standard ATA 100 controller:
>
> 5.4-STABLE Highpoint 1820a RAID 5 ( 5 disk )
> dd if=/dev/da0 of=/dev/null bs=64k count=10000
> 10000+0 records in
> 10000+0 records out
> 655360000 bytes transferred in 13.348032 secs (49097875 bytes/sec)
>
> 5.3-RELEASE Highpoint 454 RAID 5 ( 4 disk )
> dd if=/dev/da0 of=/dev/null bs=64k count=10000
> 10000+0 records in
> 10000+0 records out
> 655360000 bytes transferred in 20.410034 secs (32109697 bytes/sec)
>
> 5.2.1-RELEASE Intel ICH3 UDMA100 ( 1 disk )
> dd if=/dev/ad0 of=/dev/null bs=64k count=10000
> 10000+0 records in
> 10000+0 records out
> 655360000 bytes transferred in 11.142405 secs (58816745 bytes/sec)
>
> Obviously something is seriously a miss here somewhere as
> both the RAID 5 arrays a producing less throughput than
> a single disk.
>
> Where do I start looking?
First, understand that RAID 5 is dependant on fast hardware to performa
the XOR operations. A single disk without any RAID can easily
outperform a RAID array if the RAID array is on a 'slow' controller.
The Highpoint controllers are not exactly high-end fast RAID
controllers, so ~50MB/s isn't too bad for that I would say. Did you
happen to try a vinum RAID5? How about a stripe?
You could make two RAID 5's with the controller, and then stripe those
in vinum. You could also do a combo of two stripes in the controller,
and a vinum mirror in FreeBSD - that would give you decent performance.
Eric
-- ------------------------------------------------------------------------ Eric Anderson Sr. Systems Administrator Centaur Technology A lost ounce of gold may be found, a lost moment of time never. ------------------------------------------------------------------------ _______________________________________________ freebsd-performance@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-performance To unsubscribe, send any mail to "freebsd-performance-unsubscribe@freebsd.org"
- Previous message: Steven Hartland: "Re: Very low disk performance Highpoint 1820a"
- Maybe in reply to: Steven Hartland: "Re: Very low disk performance Highpoint 1820a"
- Next in thread: Steven Hartland: "Re: Very low disk performance Highpoint 1820a"
- Reply: Steven Hartland: "Re: Very low disk performance Highpoint 1820a"
- Reply: Arne : "Re: Very low disk performance Highpoint 1820a"
- Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
Relevant Pages
|
|
