Re: absurdly high "optimal_io_size" on Seagate SAS disk

[Dale R. Worley]

> From: Chris Friesen <chris.friesen@xxxxxxxxxxxxx>

> Also, I think it's wrong for filesystems and userspace to use it for 
> alignment.  In E.4 and E.5 in the "sbc3r25.pdf" doc, it looks like they 
> use the optimal granularity field for alignment, not the optimal 
> transfer length.

Everything you say suggests that "optimal transfer length" means
"there is a penalty for doing transfers *larger* than this", but
people have been treating it as "there is a penalty for doing
transfers *smaller* than this".  But the latter is the "optimal
transfer length granularity".

Dale
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