From: Mark Mielke <mark@mark.mielke.cc>
To: Florian Weimer <fw@deneb.enyo.de>
Cc: david@lang.hm, Fernando Hevia <fhevia@ip-tel.com.ar>
Cc: pgsql-performance <pgsql-performance@postgresql.org>
Subject: Re: With 4 disks should I go for RAID 5 or RAID 10
Date: Wed, 26 Dec 2007 16:40:40 -0500
Message-ID: <4772CA58.5050406@mark.mielke.cc> (raw)
In-Reply-To: <87zlvxnpkl.fsf@mid.deneb.enyo.de>
References: <0f8201c847f6$08e15090$8f01010a@iptel.com.ar>
<Pine.LNX.4.64.0712261317320.11785@asgard.lang.hm>
<87zlvxnpkl.fsf@mid.deneb.enyo.de>
Florian Weimer wrote:
>> seek/read/calculate/seek/write since the drive moves on after the
>> read), when you read you must read _all_ drives in the set to check
>> the data integrity.
>>
> I don't know of any RAID implementation that performs consistency
> checking on each read operation. 8-(
>
Dave had too much egg nog... :-)
Yep - checking consistency on read would eliminate the performance
benefits of RAID under any redundant configuration.
Cheers,
mark
--
Mark Mielke <mark@mielke.cc>
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To: pgsql-performance@postgresql.org
Cc: mark@mark.mielke.cc, fw@deneb.enyo.de, fhevia@ip-tel.com.ar
Subject: Re: With 4 disks should I go for RAID 5 or RAID 10
In-Reply-To: <4772CA58.5050406@mark.mielke.cc>
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