Message-ID: <4DBAE181.2000204@iathh.de>
Date: Fri, 29 Apr 2011 18:04:17 +0200
From: Joachim Worringen <joachim.worringen@iathh.de>
Organization: IAT GmbH
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To: pgsql-performance@postgresql.org
Subject: Re: FUSION-IO io cards
References: <BANLkTikdOoUZyvcNEXk67563tf7c78ZGUQ@mail.gmail.com>
	<69D96B03-F991-4825-A8FF-0FEEDCC17461@silentmedia.com>
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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