Re: [PERFORM] inferior SCSI performance

2003-10-03 Thread Vivek Khera
> "CB" == Christopher Browne <[EMAIL PROTECTED]> writes: CB> Unfortunately, while there are companies hawking SSDs, they are in the CB> "you'll have to talk to our salescritter for pricing" category, which CB> means that they must be ferociously expensive. :-(. You ain't kidding. Unfortunat

Re: [PERFORM] inferior SCSI performance

2003-10-02 Thread Ang Chin Han
Andrew Sullivan wrote: Yes. If and only if you have a battery-backed cache. I know of no IDE drives that have that, but there's nothing about the spec which makes it impossible. http://www.ussg.iu.edu/hypermail/linux/kernel/0103.0/1084.html Relevant section: Maybe that is why there is a vender

Re: [PERFORM] inferior SCSI performance

2003-10-02 Thread Greg Stark
> > Unfortunately, while there are companies hawking SSDs, they are in the > > "you'll have to talk to our salescritter for pricing" category, which > > means that they must be ferociously expensive. :-(. > > the cheapest I found was the one with external backup power was ~1.8k$ > for 2GB PCI de

Re: [PERFORM] inferior SCSI performance

2003-10-02 Thread Hannu Krosing
Christopher Browne kirjutas K, 01.10.2003 kell 19:21: > > The FS-related result appeared surprising, as the "stories" I had > heard suggested that JFS hadn't been particularly heavily tuned on > Linux, whereas XFS was supposed to be the "speed demon." Gentoo linux recommends XFS only for SAN+fib

Re: [PERFORM] inferior SCSI performance

2003-10-01 Thread Christopher Browne
[EMAIL PROTECTED] (Andrew Sullivan) writes: > On Wed, Oct 01, 2003 at 07:14:32AM -0600, scott.marlowe wrote: >> FYI, on a Dual PIV2800 with 2 gig ram and a single UDMA 80 gig hard drive, >> I from 420 tps to 22 tps when I disable write caching. WOW. A factor of >> about 20 times slower. (pgben

Re: [PERFORM] inferior SCSI performance

2003-10-01 Thread Andrew Sullivan
On Wed, Oct 01, 2003 at 07:14:32AM -0600, scott.marlowe wrote: > FYI, on a Dual PIV2800 with 2 gig ram and a single UDMA 80 gig hard drive, > I from 420 tps to 22 tps when I disable write caching. WOW. A factor of > about 20 times slower. (pgbench -c 4 -t 100) That's completely consistent wit

Re: [PERFORM] inferior SCSI performance

2003-10-01 Thread scott.marlowe
On Wed, 1 Oct 2003, Andrew Sullivan wrote: > On Wed, Sep 17, 2003 at 04:46:00PM -0400, Michael Adler wrote: > > So the quesiton is whether it is ever sensible to use write-caching and > > expect comparable persistence. > > Yes. If and only if you have a battery-backed cache. I know of no > IDE

Re: [PERFORM] inferior SCSI performance

2003-10-01 Thread Andrew Sullivan
On Wed, Sep 17, 2003 at 04:46:00PM -0400, Michael Adler wrote: > So the quesiton is whether it is ever sensible to use write-caching and > expect comparable persistence. Yes. If and only if you have a battery-backed cache. I know of no IDE drives that have that, but there's nothing about the spe

Re: [PERFORM] inferior SCSI performance

2003-09-30 Thread Michael Adler
On Wed, 17 Sep 2003, Tom Lane wrote: > Michael Adler <[EMAIL PROTECTED]> writes: > > I have been experimenting with a new Seagate Cheetah 10k-RPM SCSI to > > compare with a cheaper Seagate Barracuda 7200-RPM IDE (each in a > > single-drive configuration). The Cheetah definately dominates the gene

Re: [PERFORM] inferior SCSI performance

2003-09-17 Thread Tom Lane
Michael Adler <[EMAIL PROTECTED]> writes: > I have been experimenting with a new Seagate Cheetah 10k-RPM SCSI to > compare with a cheaper Seagate Barracuda 7200-RPM IDE (each in a > single-drive configuration). The Cheetah definately dominates the generic > IO tests such as bonnie++, but fares poor

[PERFORM] inferior SCSI performance

2003-09-17 Thread Michael Adler
I have been experimenting with a new Seagate Cheetah 10k-RPM SCSI to compare with a cheaper Seagate Barracuda 7200-RPM IDE (each in a single-drive configuration). The Cheetah definately dominates the generic IO tests such as bonnie++, but fares poorly with pgbench (and other postgresql operations)