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From: David Boreham <david_list@boreham.org>
To: pgsql-performance@postgresql.org
Subject: Re: Reliability with RAID 10 SSD and Streaming Replication
Date: Wed, 22 May 2013 11:31:51 -0600
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On 5/22/2013 8:18 AM, Greg Smith wrote:
>
> They can easily hit that number.  Or they can do this:
>
> Device:     r/s    w/s  rMB/s  wMB/s avgrq-sz avgqu-sz  await svctm  
> %util
> sdd     2702.80  19.40  19.67   0.16    14.91   273.68  71.74 0.37 100.00
> sdd     2707.60  13.00  19.53   0.10    14.78   276.61  90.34 0.37 100.00
>
> That's an Intel 710 being crushed by a random read database server 
> workload, unable to deliver even 3000 IOPS / 20MB/s.  I have hours of 
> data like this from several servers.

This is interesting. Do you know what it is about the workload that 
leads to the unusually low rps ?





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