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From: dforum <dforums@vieonet.com>
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To: Merlin Moncure <mmoncure@gmail.com>
CC: pgsql-performance@postgresql.org
Subject: Re: Plz Heeeelp! performance settings
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Tx for your reply.

You mean that RAID use fsync method for keeping data's copy.

So you invite me to desactivate fsync to increase the performance ?

Desactivating fsync. my second disk will not be uptodate, so if the 
machine crash, I wont be able to get the server working quickly??? But 
if I use a second machine to replicate the database, I escape this 
problem isn't it ?

If I understand right, could you tell me how to do desactivate fsync 
please ?

Best regards

David

Merlin Moncure a écrit :
> On Wed, Aug 6, 2008 at 6:12 PM, dforum <dforums@vieonet.com> wrote:
>   
>> Hello to all,
>>
>>
>> I have a Linux 2.6.24.2-xxxx-std-ipv4-64 #3 SMP Tue Feb 12 12:27:47 CET 2008
>> x86_64 Intel(R) Xeon(R) CPU X5355 @ 2.66GHz GenuineIntel GNU/Linux
>> with 8Gb of memory. Using sata II disk in RAID 1 (I known that is bad, but
>>     
> <snip>
>
> this is likely your problem...with fsync on (as you have it), you will
> be lucky to get a couple of hundred transactions/sec out of the
> database.  you are probably just exceeding your operational
> capabilities of the hardware so you probably need to upgrade or turn
> off fsync (which means data corruption in event of hard crash).
>
> merlin
>
>