Which is faster: iSCSI to linux box over 1Gb or local SATA storage with intel ICH9?

[Ryan Parrish]

On May 16, 2010, at 7:39 AM, Sander van Vugt wrote:

> Hi,
> 
> On Sun, 2010-05-16 at 11:14 +0000, Andy Smith wrote:
>> Hi Justin,
>> 
>> On Sat, May 15, 2010 at 11:23:19PM -0400, justino garcia wrote:
>>> Which is faster: iSCSI to linux box over 1Gb or local SATA storage with
>>> intel ICH9?
>> 
>> You'll have to benchmark for your load, but local storage is usually
>> faster than remote at least because of the lower latency.
> 
> A simple test that I like doing to measure performance data is like:
> 
> time dd if=/dev/zero of=/mountpoint/dummyfile bs=1M count=1024
> 


If your going to do this test, make sure the dummyfile is larger than your RAM (I always double it) otherwise the caching that the kernel does can skew your results.

It's also entirely possible to get iSCSI with faster transfer rates than a local drive, an array of 10 drives over iSCSI done right is probably going to beat out a single local SATA.  So you need to be a little more specific in the implementation details.

Ryan Parrish