Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1YWT1P-0007h0-4u for pgsql-admin@arkaria.postgresql.org; Fri, 13 Mar 2015 17:05:15 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.80) (envelope-from ) id 1YWT1O-0005gj-K3 for pgsql-admin@arkaria.postgresql.org; Fri, 13 Mar 2015 17:05:14 +0000 Received: from makus.postgresql.org ([2001:4800:1501:1::229]) by malur.postgresql.org with esmtps (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1YWT1N-0005fa-Nj for pgsql-admin@postgresql.org; Fri, 13 Mar 2015 17:05:13 +0000 Received: from adsltrust.ath.forthnet.gr ([194.219.204.174] helo=smadev.internal.net) by makus.postgresql.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.80) (envelope-from ) id 1YWT1K-0007Z0-KB for pgsql-admin@postgresql.org; Fri, 13 Mar 2015 17:05:11 +0000 Received: from smadev.internal.net (smadev [10.9.200.131]) by smadev.internal.net (8.14.7/8.14.7) with ESMTP id t2DH54KJ043484 for ; Fri, 13 Mar 2015 19:05:05 +0200 (EET) (envelope-from achill@matrix.gatewaynet.com) Message-ID: <550318C0.90808@matrix.gatewaynet.com> Date: Fri, 13 Mar 2015 19:05:04 +0200 From: Achilleas Mantzios User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:24.0) Gecko/20100101 Thunderbird/24.3.0 MIME-Version: 1.0 To: pgsql-admin@postgresql.org Subject: Re: Samsung SSD 850 PRO 1T : any good for PostgreSQL? References: <5502C98F.2090806@matrix.gatewaynet.com> <5502CCAF.4030606@commandprompt.com> <5502E31E.4020301@matrix.gatewaynet.com> <5502EC3F.4040900@matrix.gatewaynet.com> In-Reply-To: Content-Type: multipart/alternative; boundary="------------010707050501010207030807" X-Pg-Spam-Score: -1.9 (-) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-admin Precedence: bulk Sender: pgsql-admin-owner@postgresql.org This is a multi-part message in MIME format. --------------010707050501010207030807 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 13/03/2015 18:01, Fernando Hevia wrote: > > > On Fri, Mar 13, 2015 at 11:31 AM, Ryan Thompson > wrote: > > Personally, I'd steer clear of Samsung desktop SSDs for anything mission-critical. I've seen them get ripped apart by standard SATA controllers as well as LSI MegaRAID. My rule of thumb is > Samsung is okay as long as we're using RAID 1. > > For data loss, pick up a RAID controller card with BBU or capacitor-based cache protection. That way, in the event of a total power failure, the data integrity is maintained and simply continues > writing to disk once power is restored. > > > I am afraid that won't suffice. The HD will signal the controller that the data has been committed safely - which we know is not the case - and the controller cache data would be discarded to make > room for new blocks. > > People, thanks a lot for all your replies. I just hope I won't have to send the next message in this list in full panic mode. -- Achilleas Mantzios Head of IT DEV IT DEPT Dynacom Tankers Mgmt --------------010707050501010207030807 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 8bit
On 13/03/2015 18:01, Fernando Hevia wrote:


On Fri, Mar 13, 2015 at 11:31 AM, Ryan Thompson <agyant@gmail.com> wrote:
Personally, I'd steer clear of Samsung desktop SSDs for anything mission-critical. I've seen them get ripped apart by standard SATA controllers as well as LSI MegaRAID. My rule of thumb is Samsung is okay as long as we're using RAID 1. 

For data loss, pick up a RAID controller card with BBU or capacitor-based cache protection. That way, in the event of a total power failure, the data integrity is maintained and simply continues writing to disk once power is restored.

I am afraid that won't suffice. The HD will signal the controller that the data has been committed safely - which we know is not the case - and the controller cache data would be discarded to make room for new blocks.



People,

thanks a lot for all your replies. I just hope I won't have to send the next message in this list in full panic mode.

-- 
Achilleas Mantzios
Head of IT DEV
IT DEPT
Dynacom Tankers Mgmt
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