Re: [PATCH v2 4/4] Bump rename limit defaults (yet again)

On Wed, Jul 14, 2021 at 01:03:43PM -0700, Elijah Newren wrote:

quoted

The 2008 timings are from the old email you linked in your commit
message, and the new one is from running the revised script you showed.
The savings seem like more than 30%. I don't know if that's all CPU or
if something changed in the code.

I was using the script you wrote in 2008, but comparing to your
reported numbers in 2011[1].  When you bumped in 2011, you said you
picked the limits of 400 & 1000 in order to give rough timings of 2s
and 10s.  So the table looks more like:

   N  CPU (2008)  CPU (2011)  c5xlarge  CPU (yours)
 400    4.87s         ~2s      1.106s      0.788s
1000   27.82s        ~10s      6.350s      4.431s

So, 2011->c5xlarge on these (just recomputed now numbers) show
improvements of ~45% and ~36%.  Maybe I had an outlier run earlier
that was in the upper 6s range for N=1000 and I rounded off to 30% for
the commit message?  Don't know, those numbers are on a laptop that
died in the last few days.

Ah, right. I forgot about the 2011 update. So yeah, things are getting
faster, but not as much as I would have hoped as somebody who came of
age during the clock speed boom of the 90's. :)

Thanks for humoring my puzzlement (I don't think any of this changes the
applicability of your patch).

-Peff