[gclist] Hotspot slower on first run

Eliot Moss moss@emperor.cs.umass.edu
Tue, 19 Oct 1999 07:55:43 -0400 (EDT)

An earlier message commented that Hotspot was slower on the first run of a
(gc) benchmark, and wondered why. My guess is that it's the compilation
technology. Hotspot interprets bytecodes until/unless a method (or maybe
even a loop in a method?) is executed more than a threshold number of times
(I have heard the number 1000 whispered :-), and then it compiles the code
to native code. Of course the gc itself is presumably all in native code
:-). In any case, I do not find that behavior surprising.

-- Eliot
J. Eliot B. Moss, Associate Professor      http://www.cs.umass.edu/~moss   www
Computer Science Department, LGRC          +1-413-545-4206               voice
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