Re: [PATCH 1/2] fs: Do not dispatch FITRIM through separate super_operation

Mark Lord
2010-11-26T13:49:07Z

On 10-11-25 11:24 AM, Greg Freemyer wrote:
>
> I'm away from my systems today, but is there an easy way to tweak
> wiper.sh or hdparm to cause only a single range per trim command.
>
> I'm curious if for the Sandforce that would still be in the 90 second
> range, or closer to 64x that.

Good question. The Indilinx based drives would be in the 64x range,
no doubt there. But I don't know about the Sandforce.

And I don't think I'm willing to inflict so many life-shortening erase
cycles onto it just to find out.

One thing to note: the execution time for TRIM does vary depending upon
whether the (logical) LBAs are already mostly in a "trimmed" state or not.

So anyone aspiring to benchmark this stuff will need to keep that in mind.
My timings above were for "already trimmed" cases. I would expect them
to be much slower (2x - 3x) if the sectors all held data prior to trim.

Cheers