Re: most bang for buck with ~ $20,000

Hi Kenji,

I'm not sure what you mean by 'something newer'? The intel
woodcrest-cpu's are brand-new compared to the amd opterons. But if you
need a 4-cpu config (I take it you want 8-cores in that case), Dell
doesn't offer much. Whether something new will come, I don't know. I'm
not sure when (or if?) a MP-Woodcrest will arrive and/or when Dell will
start offering Opteron-servers.

Sas has been designed as the successor to SCSI.

As I see it, SAS has currently one major disadvantage. Lots of new
servers are equipped with SAS-drives, a few nice SAS-raidcontrollers
exist, but the availability of external enclosures for SAS is not
widespread yet. So your options of going beyond (say) 8 disks per system
are a bit limited.

There are of course advantages as well. The bus is much wider (you can
have 4 lanes of 3Gbps each to an enclosure). You can mix sas and sata
disks, so you could have two arrays in the same enclosure, one big
storage bin and a very fast array or just use only sata disks on a sas
controller. The cabling itself is also much simpler/more flexible
(although using a hot-plug enclosure of course shields you mostly from
that).
But whether its the right choice to make now? I'm not sure. We weren't
to fond of investing a lot of money in an end-of-life system. And since
we're a tech-website, we also had to worry about our "being modern
image", of course ;)

The main disadvantage I see in this case is, as said, the limited
availability of external enclosures in comparison to SCSI and Fibre
Channel. HP currently only offers their MSA50 (for the rather expensive
SFF disks) while their MSA60 (normal disks) will not be available until
somewhere in 2007 and Dell also only offers one enclosure, the MD1000.
The other big players offer nothing yet, as far as I know, while they
normally offer several SCSI and/or FC-enclosures.
There are also some third-party enclosures (adaptec and promise for
instance) available of course.

Best regards,

Arjen

On 18-8-2006 21:07, Kenji Morishige wrote:
> Thanks Arjen,
> I have unlimited rack space if I really need it.  Is serial/SAS really the
> better route to go than SCSI these days? I'm so used to ordering SCSI that
> I've been out of the loop with new disk enclosures and disk tech.  I been
> trying to price out a HP DL585, but those are considerably more than the
> Dells.  Is it worth waiting a few more weeks/months for Dell to release
> something newer?
>
> -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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>>>
>