From: Roberto Spadim <roberto@spadim.com.br>
To: Phillip Susi <psusi@cfl.rr.com>
Cc: David Brown <david@westcontrol.com>, linux-raid@vger.kernel.org
Subject: Re: SSD - TRIM command
Date: Mon, 21 Feb 2011 15:25:03 -0300 [thread overview]
Message-ID: <AANLkTim6qJRZABYj4y_1sL6xq7y_w-STbaC4MK3U05ug@mail.gmail.com> (raw)
In-Reply-To: <4D62ACFE.4020401@cfl.rr.com>
TRIM is a new feature for many hard disk/ssd
it´s more to get a bigger life o disk, allow a dynamic badblock
reallocation (filesystem must tell where is empty)
2011/2/21 Phillip Susi <psusi@cfl.rr.com>:
> On 2/9/2011 10:49 AM, David Brown wrote:
>> I've been reading a little more about this. It seems that the days of
>> TRIM may well be numbered - the latest generation of high-end SSDs have
>> more powerful garbage collection algorithms, together with more spare
>> blocks, making TRIM pretty much redundant. This is, of course, the most
>> convenient solution for everyone (as long as it doesn't cost too much!).
>>
>> The point of the TRIM command is to tell the SSD that a particular block
>> is no longer being used, so that the SSD can erase it in the background
>> - that way when you want to write more data, there are more free blocks
>> ready and waiting. But if you've got plenty of spare blocks, it's easy
>> to have them erased in advance and you don't need TRIM.
>
> It is not just about having free blocks ready and waiting. When doing
> wear leveling, you might find an erase block that has not been written
> to in a long time, so you want to move that data to a more worn block,
> and use the less worn block for more frequently written to sectors. If
> you know that sectors are unused because they have been TRIMed, then you
> don't have to waste time and wear copying the junk there to the new
> flash block.
>
> TRIM is also quite useful for thin provisioned storage, which seems to
> be getting popular.
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--
Roberto Spadim
Spadim Technology / SPAEmpresarial
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next prev parent reply other threads:[~2011-02-21 18:25 UTC|newest]
Thread overview: 70+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-02-07 20:07 SSD - TRIM command Roberto Spadim
2011-02-08 17:37 ` maurice
2011-02-08 18:31 ` Roberto Spadim
[not found] ` <AANLkTik5SumqyTN5LZVntna8nunvPe7v38TSFf9eCfcU@mail.gmail.com>
2011-02-08 20:50 ` Roberto Spadim
2011-02-08 21:18 ` maurice
2011-02-08 21:33 ` Roberto Spadim
2011-02-09 7:44 ` Stan Hoeppner
2011-02-09 9:05 ` Eric D. Mudama
2011-02-09 15:45 ` Chris Worley
2011-02-09 13:29 ` David Brown
2011-02-09 14:39 ` Roberto Spadim
2011-02-09 15:00 ` Scott E. Armitage
2011-02-09 15:52 ` Chris Worley
2011-02-09 19:15 ` Doug Dumitru
2011-02-09 19:22 ` Roberto Spadim
2011-02-09 16:19 ` Eric D. Mudama
2011-02-09 16:28 ` Scott E. Armitage
2011-02-09 17:17 ` Eric D. Mudama
2011-02-09 18:18 ` Roberto Spadim
2011-02-09 18:24 ` Piergiorgio Sartor
2011-02-09 18:30 ` Roberto Spadim
2011-02-09 18:38 ` Piergiorgio Sartor
2011-02-09 18:46 ` Roberto Spadim
2011-02-09 18:52 ` Roberto Spadim
2011-02-09 19:13 ` Piergiorgio Sartor
2011-02-09 19:16 ` Roberto Spadim
2011-02-09 19:21 ` Piergiorgio Sartor
2011-02-09 19:27 ` Roberto Spadim
2011-02-21 18:24 ` Phillip Susi
2011-02-21 18:30 ` Roberto Spadim
2011-02-09 15:49 ` David Brown
2011-02-21 18:20 ` Phillip Susi
2011-02-21 18:25 ` Roberto Spadim [this message]
2011-02-21 18:34 ` Phillip Susi
2011-02-21 18:48 ` Roberto Spadim
2011-02-21 18:51 ` Mathias Burén
2011-02-21 19:32 ` Roberto Spadim
2011-02-21 19:38 ` Mathias Burén
2011-02-21 19:39 ` Mathias Burén
2011-02-21 19:43 ` Roberto Spadim
2011-02-21 20:45 ` Phillip Susi
2011-02-21 19:39 ` Roberto Spadim
2011-02-21 19:51 ` Doug Dumitru
2011-02-21 19:57 ` Roberto Spadim
2011-02-21 20:47 ` Phillip Susi
2011-02-21 21:02 ` Mathias Burén
2011-02-21 22:52 ` Roberto Spadim
2011-02-21 23:41 ` Mathias Burén
2011-02-21 23:42 ` Mathias Burén
2011-02-21 23:52 ` Roberto Spadim
2011-02-22 0:25 ` Mathias Burén
2011-02-22 0:30 ` Brendan Conoboy
2011-02-22 0:36 ` Eric D. Mudama
2011-02-22 1:46 ` Roberto Spadim
2011-02-22 1:52 ` Mathias Burén
2011-02-22 1:55 ` Roberto Spadim
2011-02-22 2:01 ` Eric D. Mudama
2011-02-22 2:02 ` Mikael Abrahamsson
2011-02-22 2:22 ` Guy Watkins
2011-02-22 2:27 ` Roberto Spadim
2011-02-22 3:45 ` NeilBrown
2011-02-22 4:37 ` Roberto Spadim
2011-02-22 2:38 ` Phillip Susi
2011-02-22 3:29 ` Roberto Spadim
2011-02-22 3:42 ` Roberto Spadim
2011-02-22 4:04 ` Phillip Susi
2011-02-22 4:30 ` Roberto Spadim
2011-02-22 14:45 ` Phillip Susi
2011-02-22 17:15 ` Roberto Spadim
2011-02-22 0:32 ` Eric D. Mudama
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