Re: RAID + PostgreSQL?

Of course if you really want good performance, 6 drives is a little light,
and U320 is definatley not the way to go as you are limited to 320MB/sec per
channel (an the DL380 comes with all drives on one channel) (not that you
could saturate that with only 6 drives in RAID 10 anyway). Given that this
chap has 13 disks already, a DL380 is probably not what he is looking for.
Consider SAS for better performance.

Alex

On 6/28/06, Franz(dot)Rasper(at)izb(dot)de <Franz(dot)Rasper(at)izb(dot)de> wrote:
>
> How much I/O Performance do you need ?
>
> READ Performance ? Write Performance ?
>
> I need an fast and reliable RAID Controller (harddisks have to be hot
> plug,
> automatic rebuild etc.)
> and I have to say that the HP DL 380 G 4 with Battery Backup Write Cache ,
> FAST U320 HDs,
> some gigs ram (chipkill is a nice feature), redundant fans and power
> supplies is a good database server.
> Unfortunately I had no chance to test the HP DL 385.
>
> Greetings,
>
> -Franz
>
> -----Ursprüngliche Nachricht-----
> Von: Scott Marlowe [mailto:smarlowe(at)g2switchworks(dot)com]
> Gesendet: Dienstag, 27. Juni 2006 17:45
> An: Franz(dot)Rasper(at)izb(dot)de
> Cc: teolupus(at)gmail(dot)com; pgsql general
> Betreff: Re: [GENERAL] RAID + PostgreSQL?
>
>
> On Tue, 2006-06-27 at 08:05, Franz(dot)Rasper(at)izb(dot)de wrote:
> > I have here HP DL 380 G3 und HP DL 380 G4. (here Smart Array 5i and
> Smart
> > Array 6i)
> > Maybe there are problems with old linux kernel (but as far as i know >
> > 2.4.27)
> > I dont know about such performance problems, maybe the conrollers are
> faster
> > under windows.
> >
> > The battery backup write cache are very import for inserts.
> >
> > You should use for performance test with dd under linux larger
> blocksizes,
> > but you should compare postgresql under linux and windows (selects,
> update,
> > inserts, etc.)
>
> Note that having the latest driver usually helps a lot too.
>
> The LSI megaraid was solid but a mediocre performer with the older 1.18
> driver, but the 2.x series driver was much faster when I tested it.
>
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