Re: I/O tests using elvtune to improve interactive performance

[rwhron@earthlink.net]

On Mon, Nov 19, 2001 at 08:09:22AM +0100, Jens Axboe wrote:
> > Test:	Run growfiles tests from Linux Test Project that really hurt
> > 	interactive performance.  Simultaneously run "ls -laR /".
> > 	Change the elevator read latency value with elvtune.
> > 	Also run mp3blaster tests.
> 
> Interesting tests, thanks. I wonder if you could be convinced to do
> bonnie++ and dbench tests with the same read_latency values used? Also,
> I'm assuming you kept write latency at its default of 16384?
> -- 
> Jens Axboe
> 

Thanks for the feedback.  Write latency was 16384 for all tests.

I'm downloading dbench and bonnie++ now.   I'll check them out.

I'm still not sure how to measure/quantify interactive performance.  

My ideal test will have these components:

1) Simulate and measure user interactive response time.
2) Disk I/O patterns capable of making interactive performance slow.
3) Measurement of I/O throughput.
4) Note how changes with elvtune effect throughput and response time.
5) It's not too boring.  (i.e. type something, use a stop watch).

It's the "measure interactive response time" that I haven't got a handle 
on yet.  I'm looking at the SSBA benchmarks for something that simulates 
users.  I don't know if it measures response time.

I could resort to a stopwatch to test interactive response, but
hopefully, something better will come to mind.
-- 
Randy Hron