Re: most bang for buck with ~ $20,000 - Mailing list pgsql-performance

We were in a similar situation with a similar budget. But we had two
requirements, no "deprecated" scsi while the successor SAS is available
and preferrably only 3 or 4U of rack space. And it had to have
reasonable amounts of disks (at least 12).

The two options we finally choose between where a Dell 1U 1950 with two
woodcrests 5160 (I don't think the older dempsey 50x0's are a good idea)
and 16GB of memory combined with a PowerVault MD1000 external storage
SAS JBOD unit, with 15 36GB 15k rpm disks and from HP a similar
configured DL360G5 (also 1U) combined with two MSA50 SFF SAS JBOD
enclosures with 20 36GB 10k rpm SFF disks.

Both enclosures offer has SAS-connectivity (serial attached scsi), i.e.
the "next generation scsi". Which is supposed to be the successor to
scsi, but unfortunately its not yet as widely available.

The Dell MD1000 is 3U high and can be fitted with 15 3.5" disks, the
MSA50 is 1U and can be fitted with 10 2.5" disks.
In terms of performance you'll likely need two MSA50's to be up to par
with one MD1000. The SFF disks are about as expensive as the 15k 3.5"
disks... so its mostly interesting for packing a lot of I/O in a small
enclosure. HP is going to offer a 3.5" SAS-enclosure (MSA60) but that
one won't be available until Q1 2007 or something like that.
As said Promise and Adaptec also offer SAS enclosures, both are 2U and
can be fitted with 12 disks. There are more available, but they are
generally quite bit hard to find.

Good luck with your search.

Best regards,

Arjen


Kenji Morishige wrote:
> I have unlimited rack space, so 2U is not the issue. The boxes are stored in
> our lab for internal software tools.  I'm going to research those boxes you
> mention.  Regarding the JBOD enclosures, are these generally just 2U or 4U
> units with SCSI interface connectors?  I didn't see these types of boxes
> availble on Dell website, I'll look again.
> -Kenji
>
> On Wed, Aug 09, 2006 at 07:35:22AM +0200, Arjen van der Meijden wrote:
>> With such a budget you should easily be able to get something like:
>> - A 1U high-performance server (for instance the Dell 1950 with 2x
>> Woodcrest 5160, 16GB of FB-Dimm memory, one 5i and one 5e perc raid
>> controller and some disks internally)
>> - An external SAS direct attached disks storage enclosure full with 15k
>> rpm 36GB disks (for instance the MD1000, with 15x 36GB 15k disks)
>>
>> Going for the dell-solution would set you back "only" (including
>> savings) about $13-$14k. HP offers a similar solutions (a HP DL360G5 or
>> a DL380G5/DL385 with two MSA50's for instance) which also fit in your
>> budget afaik. The other players tend to be (a bit) more expensive, force
>> you to go with Fibre Channel or "ancient" SCSI external storage ;)
>>
>> If you'd like to have a product by a generic vendor, have a look at the
>> Adaptec JS50 SAS Jbod enclosure or Promise's Vtrak 300 (both offer 12
>> sas/sata bays in 2U) for storage.
>>
>> If you're limited to only 2U of rack space, its a bit more difficult to
>> get maximum I/O in your budget (you have basically space for about 8 or
>> 12 3.5" disks (with generic suppliers) or 16 2.5" sff disks (with HP)).
>> But you should still be able to have two top-off-the-line x86 cpu's (amd
>> opteron 285 or intel woorcrest 5160) and 16GB of memory (even FB Dimm,
>> which is pretty expensive).
>>
>> Best regards,
>>
>> Arjen van der Meijden
>>
>>
>> On 8-8-2006 22:43, Kenji Morishige wrote:
>>> I've asked for some help here a few months ago and got some really helpfull
>>> answers regarding RAID controllers and server configuration.  Up until
>>> recently I've been running PostgreSQL on a two year old Dual Xeon 3.06Ghz
>>> machine with a single channel RAID controller (previously Adaptec 2200S,
>>> but
>>> now changed to LSI MegaRAID). The 2U unit is from a generic vendor using
>>> what
>>> I believe is a SuperMicro motherboard.  In the last week after upgrading
>>> the
>>> RAID controller, the machine has had disk failure and some other issues. I
>>> would like to build a very reliable dedicated postgreSQL server that has
>>> the
>>> ultimate possible performance and reliabily for around $20,000.  The data
>>> set
>>> size is only currently about 4GB, but is increasing by approximately 50MB
>>> daily.  The server also requires about 500 connections and I have been
>>> monitoring about 100-200 queries per second at the moment.  I am planning
>>> to
>>> run FreeBSD 6.1 if possible, but I am open to any other suggestions if it
>>> improves performance.
>>>
>>> I am considering a setup such as this:
>>>  - At least dual cpu (possibly with 2 cores each)
>>>  - 4GB of RAM
>>>  - 2 disk RAID 1 array for root disk
>>>  - 4 disk RAID 1+0 array for PGDATA
>>>  - 2 disk RAID 1 array for pg_xlog
>>>
>>> Does anyone know a vendor that might be able provide such setup?  Any
>>> critique in this design? I'm thinking having a 2 channel RAID controller to
>>> seperate the PGDATA, root and pg_xlog.
>>>
>>> Sincerely,
>>> Kenji
>>>
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>