TMS RAMSAN is a DRAM device. TMS built DRAM SSDs going back decades, but have recently gotten into flash SSDs as well.
The DRAM parts are in an order of magnitude more expensive than others' flash SSDs, gig by gig. Also, about as fast as
offcpu storage gets.
regards,
Robert
---- Original message ----
>Date: Fri, 29 Apr 2011 18:04:17 +0200
>From: pgsql-performance-owner@postgresql.org (on behalf of Joachim Worringen <joachim.worringen@iathh.de>)
>Subject: Re: [PERFORM] FUSION-IO io cards
>To: pgsql-performance@postgresql.org
>
>On 04/29/2011 04:54 PM, Ben Chobot wrote:
>> We have a bunch of their cards, purchased when we were still on 8.1 and
>> were having difficulty with vacuums. (Duh.) They helped out a bunch for
>> that. They're fast, no question about it. Each FusionIO device (they
>> have cards with multiple devices) can do ~100k iops. So that's nifty.
>>
>> On the downside, they're also somewhat exotic, in that they need special
>> kernel drivers, so they're not as easy as just buying a bunch of drives.
>> More negatively, they're $$$. And even more negatively, their drivers
>> are inefficient - expect to dedicate a CPU core to doing whatever they
>> need done.
>
>I would recommend to have a look a Texas Memory Systems for a
>comparison. FusionIO does a lot of work in software, as Ben noted
>correctly, while TMS (their stuff is called RAMSAN) is a more
>all-in-hardware device.
>
>Haven't used TMS myself, but talked to people who do know and their
>experience with both products is that TMS is problem-free and has a more
>deterministic performance. And I have in fact benchmarked FusionIO and
>observed non-deterministic performance, which means performance goes
>down siginificantly on occasion - probably because some software-based
>house-keeping needs to be done.
>
>--
>Joachim Worringen
>Senior Performance Architect
>
>International Algorithmic Trading GmbH
>
>
>--
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