From: Shaun Thomas <sthomas@optionshouse.com>
To: Vitalii Tymchyshyn <tivv00@gmail.com>
Cc: Niels Kristian Schjødt <nielskristian@autouncle.com>
Cc: Kevin Grittner <kgrittn@mail.com>
Cc: pgsql-performance@postgresql.org
Cc: Willem Leenen <willem_leenen@hotmail.com>
Subject: Re: Optimize update query
Date: Fri, 30 Nov 2012 08:06:48 -0600
Message-ID: <50B8BD78.9050805@optionshouse.com> (raw)
In-Reply-To: <CABWW-d0OAT7L0beYR160jieG4=-PMHhmiMVMh=v3pNYspd9XCA@mail.gmail.com>
References: <20121130012426.69300@gmx.com>
<C5E296A1-F820-4B04-9DBD-E78380BD3300@autouncle.com>
<855F8817-6C9A-4EFB-BB80-752BF7B73B56@autouncle.com>
<CABWW-d0OAT7L0beYR160jieG4=-PMHhmiMVMh=v3pNYspd9XCA@mail.gmail.com>
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On 11/30/2012 02:37 AM, Vitalii Tymchyshyn wrote:
> Actually, what's the point in putting logs to ssd? SSDs are good for
> random access and logs are accessed sequentially.
While this is true, Niels' problem is that his regular HDs are getting
saturated. In that case, moving any activity off of them is an improvement.
Why not move the data to the SSDs, you ask? Because he bought two 3TB
drives. The assumption here is that a 256GB SSD will not have enough
space for the long-term lifespan of this database.
Either way, based on the iostat activity he posted, clearly there's some
other write stream happening we're not privy to.
--
Shaun Thomas
OptionsHouse | 141 W. Jackson Blvd. | Suite 500 | Chicago IL, 60604
312-444-8534
sthomas@optionshouse.com
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Cc: sthomas@optionshouse.com, tivv00@gmail.com, nielskristian@autouncle.com, kgrittn@mail.com, willem_leenen@hotmail.com
Subject: Re: Optimize update query
In-Reply-To: <50B8BD78.9050805@optionshouse.com>
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