Re: Performance tuning

Jens-S. Voeckler wrote:

> You got me. I was off by 2**10 in my calculations. So now, with your
> explaination of 416 MB per CD I got to revisit my numbers. Thank you:

I suspected you had somewhat larger cache than 128 MB..

> Using L1=128 as my first estimation - *before* seeing your formula - was
> not too far off the mark. Would 192 be a safe bet, or should I go straight
> for 256? In other words, is squid using steps in powers of 2 and some
> (faster) and/or/shift algebra, or are numbers like 160 legal because squid
> uses modulus algebra?

Squid is using modulus, with the undesired effect that if you have to
few L1 directories then it will wrap around on top of the first, makeing
the distribution somewhat skewed.

Note that you cannot change L1 to correct this once it has wrapped
around. Doing so would make Squid forget any objects stored in the
"wrong" L1 directories (it will eventually be cleaned, but it takes
quite a bit of time)

/Henrik
Received on Tue Nov 23 1999 - 16:40:24 MST