CPU & RAM in a storage box

[Hetz Ben Hamo]

Hi,

2010/9/9 Etzion Bar-Noy <ezaton at tournament.org.il>

> This is a joke, right? You want someone to host your system, which, by
> design, will not be rack-mountable, and would be large, due to the amount of
> disks you are to place there. It is possible, but extremely expensive to
> host a non-1-U server nowadays. Who would "give" it to you?


Huh? Of course it will be rack-mountable. I'm planning to put it on a 2U or
3U chassis.  I'm also not looking for someone to host my hardware, I already
got a rack in Netvision today.


> An industrial-grade, 2U system could host, today, about 6 3.5" SATA disks.
> A 3 U can do much more, with up to 12-14 disks, depending on the system.
>

IBM EXP 3000 can host 12 3.5" hard drives on a 2U chassis. See
this<ftp://public.dhe.ibm.com/common/ssi/ecm/en/tsd03025usen/TSD03025USEN.PDF>PDF
file. There are other 2U cases which can  host 12 3.5" disks.

And RAM is extremely important. Since you will not invest in an
> industial-class RAID controller (3ware, LSI-Logic, Adaptec, Intel, etc)
> which will cost several hundreds of dollars, as I see it, you would want to
> compensate for the high write latency with a large amount of RAM and fully
> buffered writes (not secure, but good enough). Especially with 7200RPM SATA
> drives with low seek speed.
> NFS shares, in "async" mode would give great performance, provided you give
> the system enough RAM. Then your RAM will actually become the disk write
> cache.
>

Since this machine will not be using any Xeon with it's expensive RAM, I
could put some gigs of RAM quite easily.

Thanks for your points.
Hetz

>
>
Ez
>
> 2010/9/9 Hetz Ben Hamo <hetzbh at gmail.com>
>
>> Hi,
>>
>>
>> 2010/9/9 geoffrey mendelson <geoffreymendelson at gmail.com>
>>
>>
>>> On Sep 9, 2010, at 6:35 PM, Hetz Ben Hamo wrote:
>>>
>>>
>>>> I'm planning to add some big storage solution to my VPS business. I did
>>>> some checking and calculated the costs, and figured out that if I want to
>>>> have a decent 12TB solution NAS box, it would be best if I would roll my
>>>> own. (12 TB before all the RAID stuff, after that it would lot less). All
>>>> other solutions are very expensive (example: IBM EXP 3000 costs here 6K nis
>>>> without a single hard disk).
>>>>
>>>>
>>> The question you should be asking yourself, IMHO, is what can I buy that
>>> will be as reliable as a commerical, "industrial grade" server?
>>
>>
>> Not looking for industrial grade one.
>>
>>>
>>>  I'm planning to use hardware based RAID card, minimal Linux distribution
>>>> and have some offers like iSCSI, NFS, CIFS - the usual suspects.
>>>>
>>>> My question is: since I'll use hardware RAID card, which processor and
>>>> how much RAM should I put in such a machine? Xeon is overkill IIRC.
>>>>
>>>
>>> For example, a system which costs under 900 NIS would do the job. You can
>>> get them from Ivory or KSP. They have a dual core ATOM processor,
>>> one PCI slot and one DDR2 memory slot. The power supply is not very big,
>>> but it will power a bunch of 5400 rpm "green" disks.
>>>
>>
>>
>> This storage will be mainly used for backups. If someone wants to do a
>> colocation to my rack, I want to give him a bonus, something that you can't
>> find today with my competitors: I want to give him 50-100GB for storage.
>> You'll get an NFS/CIFS/iSCSI and you mount it to your machine and use it for
>> your backup/rsync/whatever. By comparison, when you colocate a server to
>> Netvision's farm, you get ... 5GB backup space.. yippee..
>>
>>
>>> How well will it work? How long will it last? Will it be fast enough?
>>>
>>
>>  "Fast" doesn't matter much when you're doing backups or storing some
>> temporary stuff, does it really matter when it take 20 seconds instead of 10
>> when you're doing rsync? I don't think so..
>>
>>
>>> And the "killer" question, how much will it cost to replace, in the value
>>> of downtime, your time to replace it, bad will among your customers, etc?
>>>
>>
>> Really depends. I'm not planning to fully use all the disks, some will be
>> disconnected or out of the RAID, perhaps I'll put a redundant PSU.
>>
>> Hetz
>>
>>
>>> Geoff.
>>>
>>> --
>>> Geoffrey S. Mendelson,  N3OWJ/4X1GM
>>> To help restaurants, as part of the "stimulus package", everyone must
>>> order dessert. As part of the socialized health plan, you are forbidden to
>>> eat it. :-)
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>
>> --
>> my blog (hebrew): http://benhamo.org
>> Skype: heunique
>> MSN: hetz-blog at benhamo.org
>>
>> _______________________________________________
>> Linux-il mailing list
>> Linux-il at cs.huji.ac.il
>> http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
>>
>>
>

-- 
my blog (hebrew): http://benhamo.org
Skype: heunique
MSN: hetz-blog at benhamo.org
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.cs.huji.ac.il/pipermail/linux-il/attachments/20100910/1420db08/attachment.html>