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From: Erwan Velu <erwan@enovance.com>
To: Kim Holmebakken <kim.holmebakken@hotmail.com>
Cc: fio@vger.kernel.org
Subject: Re: Fio giving iops results that are equal to RAM speeds
Date: Wed, 07 May 2014 11:12:13 +0200	[thread overview]
Message-ID: <5369F8ED.4070807@enovance.com> (raw)
In-Reply-To: <BLU436-SMTP218F8CEFE3A8ED088644478E54E0@phx.gbl>


Le 07/05/2014 10:58, Kim Holmebakken a �crit :
> I tried running with the size=24G since the memory on the server is at 
> 12GB, this reduced the iops, however the MB/s is now reduced from 
> 2000+ MB/s, and now running on 850 MB/s
>
> Still i think this might be a bit high? 

If you do random IOs there is still a great chance of having cache hits. 
This number have to be put in comparison with the network bandwidth.

If you have a 1Gbit connection ... 850 is clearly hitting lot of cache.

  parent reply	other threads:[~2014-05-07  9:12 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-05-07  7:45 Fio giving iops results that are equal to RAM speeds Kim Holmebakken
2014-05-07  8:02 ` Erwan Velu
     [not found]   ` <BLU436-SMTP1086A621DD12787F2EECD40E54E0@phx.gbl>
2014-05-07  8:27     ` Erwan Velu
     [not found]       ` <BLU436-SMTP218F8CEFE3A8ED088644478E54E0@phx.gbl>
2014-05-07  9:12         ` Erwan Velu [this message]
2014-05-07 14:21       ` Jens Axboe
2014-05-07  8:10 ` puvi

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