3. That said, this could be handy. But it would be even more handy if you
could get Gaussian random numbers with \setrandom, so that you could use this
with custom scripts. And once you implement that, do we actually need the -g
flag anymore? If you want TPC-B transactions with gaussian distribution, you
can write a custom script to do that. The documentation includes a full
script that corresponds to the built-in TPC-B script.
So what I'd actually like to see is \setgaussian, for use in custom scripts.
Indeed, great idea! That looks pretty elegant! It would be something like:
\setgauss var min max sigma
I'm not sure whether sigma should be relative to max-min, or absolute.
I would say relative is better...
A concerned I raised is that what one should really want is a "pseudo
randomized" (discretized) gaussian, i.e. you want the probability of each
value along a gaussian distribution, *but* no direct frequency correlation
between neighbors. Otherwise, you may have unwanted/unrealistic positive
cache effects. Maybe this could be achieved by an independent built-in,
say either:
\randomize var min max [parameter ?]
\randomize var min max val [parameter]
Which would mean take variable var which must be in [min,max], and apply a
pseudo-random transformation which results is also in [min,max].
From a probabilistic point of view, it seems to me that a randomized
(discretized) exponential would be more significant to model a server
load.
\setexp var min max lambda...
--
Fabien.
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