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Date: Sat, 05 Jun 2010 09:55:06 -0700
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Subject: Re: sysbench / fileio - Linux vs. FreeBSD
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All of these tests have been apples vs. oranges for years.

The following seems to be true, though:

a) FreeBSD sequential write performance in UFS has always been less than 
optimal.

b) Linux sequential write performance in just about any filesystem has 
always been "impressive". But that "impressive" has come at some not so 
obvious costs. First of all, Linux is probably the most aggressive 
cluster/write-behind OS I've even seen. You can suck down all available 
memory with writebehind using dd. This means that some stats are 
"impressive", and others are "painful". A desktop that becomes 
completely unresponsive while you're doing this dd is one personal outcome.

Also, you have to be careful what you're asking for in comparing the two 
platforms, or any platforms for that matter. What do you want to 
optimize for? Apparent responsiveness as a desktop? A specific workload 
(nfs, cifs) that completes N quatloos per fortnight?