Re: RAID + PostgreSQL?

If you need so much performance and space you will need an external storage
extensions (how about SAN)
or HP ML 570 G4 (up to 18 hpt plug SFF Drives) with Intel 7041 CPUs ?

Greetings,

-Franz

-----Ursprüngliche Nachricht-----
Von: Alex Turner [mailto:armtuk(at)gmail(dot)com]
Gesendet: Dienstag, 4. Juli 2006 04:10
An: Franz(dot)Rasper(at)izb(dot)de
Cc: smarlowe(at)g2switchworks(dot)com; pgsql-general(at)postgresql(dot)org
Betreff: Re: [GENERAL] 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 <mailto:Franz(dot)Rasper(at)izb(dot)de>
<Franz(dot)Rasper(at)izb(dot)de <mailto: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: <mailto:smarlowe(at)g2switchworks(dot)com>
smarlowe(at)g2switchworks(dot)com]
Gesendet: Dienstag, 27. Juni 2006 17:45
An: Franz(dot)Rasper(at)izb(dot)de <mailto:Franz(dot)Rasper(at)izb(dot)de>
Cc: teolupus(at)gmail(dot)com <mailto: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
<mailto: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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