Compared performance of Varnish Cache on x86_64 and aarch64

[Poul-Henning Kamp]

--------
Martin Grigorov writes:

> > > Any feedback and ideas how to tweak it (VCL or even patches) are very
> > > welcome!
> >
> > First you need to tweak your benchmark setup.
> >
> >    aarch64
> >
> >           Thread Stats   Avg      Stdev     Max   +/- Stdev
> >             Latency   655.40us  798.70us  28.43ms   90.52%
> >
> > Strictly speaking, you cannot rule out that the ARM machine
> > sends responses before it receives the request, because your
> > standard deviation is larger than your average.
> >
>
> Could you explain in what case(s) the server would send responses before
> receiving a request ?

It never would, that's the point!

Your measurement says that there is 2/3 chance that the latency
is between:

	655.40µs - 798.70µs	= -143.30µs

and
	655.40µs + 798.70µs	= 1454.10µs

You cannot conclude _anything_ from those numbers.


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