[MUD-Dev] PRNGs: Pseudo Random Number Generators

[J C Lawrence]

There has been minor discussion here of the choice of PRNG's for
servers, and the impact of their NON-random properties on the server
and game.  Depending on the server design and PRNG call
characteristics this can be a really mucky area of analyse (for
instance I can and do have many threads calling the PRNG in parallel
and pseudo-random and non-deterministic order).

The Mersenne Twister may be a valuable, and computationally cheap
approach:

URL:http://www.math.keio.ac.jp/~matumoto/emt.html


--<cut>--

What is Mersenne Twister? 

Mersenne Twister(MT) is a pseudorandom number generator developped by
Makoto Matsumoto and Takuji Nishimura (alphabetical order) during
1996-1997. MT has the following merits:

-- It is designed with consideration on the flaws of various existing
generators.

-- The algorithm is coded into a C source downloadable below.

-- Far longer period and far higher order of equidistribution than any
other implemented generators. (It is proved that the period is
2^19937-1, and 623-dimensional equidistribution property is assured.)

-- Fast generation. (Although it depends on the system, it is reported
that MT is sometimes faster than the standard ANSI-C library in a
system with pipeline and cache memory.)

-- Efficient use of the memory. (The implemented C-code mt19937.c
consumes only 624 words of working area.)

--<cut>--

Originally noted on SlashDot
URL:http://www.slashdot.org/articles/9807090958246.shtml.

--
J C Lawrence                               Internet: claw at null.net
(Contractor)                               Internet: coder at ibm.net
---------(*)                     Internet: claw at under.engr.sgi.com
...Honourary Member of Clan McFud -- Teamer's Avenging Monolith...