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Date: Wed, 24 Aug 2011 21:54:48 +0200
Subject: Re: Reports from SSD purgatory
From: "Tomas Vondra" <tv@fuzzy.cz>
To: "Merlin Moncure" <mmoncure@gmail.com>
Cc: "Tomas Vondra" <tv@fuzzy.cz>, gnuoytr@rcn.com,
	pgsql-performance@postgresql.org
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On 24 Srpen 2011, 21:41, Merlin Moncure wrote:
> On Wed, Aug 24, 2011 at 2:32 PM, Tomas Vondra <tv@fuzzy.cz> wrote:
>> On 24 Srpen 2011, 20:48, gnuoytr@rcn.com wrote:
>>> Also, given that PG is *nix centric and support for TRIM is win
>>> centric,
>>> having that makes a big difference in performance.
>>
>> Windows specific? What do you mean? TRIM is a low-level way to tell the
>> drive 'this block is empty and may be used for something else' - it's
>> just
>> another command sent to the drive. It has to be supported by the
>> filesystem, though (e.g. ext4/btrfs support it).
>
> Well, it's a fair point that TRIM support is probably more widespread
> on windows.

AFAIK the only versions that supports it natively are Windows 7 and
Windows Server 2008 R2 - with other versions you're stuck with
command-line tools equal to wiper.sh or hdparm. So I don't see a
significant difference here - with a reasonably new systems (at least
kernel 2.6.33), the support is about the same.

Obviously there more machines with Windows, especially in the field of
desktop/laptop, but that does not make the TRIM Windows-specific I guess.
Most of them runs old versions (without TRIM support) anyway.

Tomas