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[REBOL] Re: byte frequencies

From: joel:neely:fedex at: 6-Jul-2001 23:17

Jeff Kreis wrote:
> I think benchmarks that involve performance impacted by > potential page faults are more meaningful when accompanied > by the test system memory stats (available system ram, etc.) >
Good point. Another reason for doing so is that I've found a few cases where relative benchmarks give different results on different platforms. I ran these on PentiumII, 108Mb RAM, RedHat 7.1, View I typically check for performance issues separately from running the timings, to minimize Heisenberg, but re-ran a few checks for the following. Via another xterm during the 8Mb test, top showed rebol using 90%-95% CPU, 7.5% of memory, with over 13Mb mem free and swap doing basically nothing. Most of the time there were 2-4 processes running (REBOL, top, X, and xterm, in that order). Rerunning the tests with that extra load increased the wall time by a few percent, but the relative performances of the three versions stayed consistent with the earlier figures. There's no rocket science here at all, but if anyone is curious enough to run identical tests on other platforms, the test rig was (function bodies deleted for space, they're in the earlier post): charfreq: make object! [ totdir: array/initial 256 0 totcpy: array/initial 256 0 totbuf: array/initial 256 0 cfdir: func [fn [file!] /local fi ch] [...] cfcpy: func [fn [file!] /local fi mybuf ch] [...] cfbuf: func [fn [file!] /local ch] [...] timetest: func [fn [file!] n [integer!] /local t0 t1 t2] [ t0: now/time loop n [cfdir fn] t1: now/time loop n [cfcpy fn] t2: now/time loop n [cfbuf fn] t3: now/time t3: t3 - t2 t3: t3/hour * 60 + t3/minute * 60 + t3/second t2: t2 - t1 t2: t2/hour * 60 + t2/minute * 60 + t2/second t1: t1 - t0 t1: t1/hour * 60 + t1/minute * 60 + t1/second t0: min min t1 t2 t3 print [ t1 tab t1 / t0 newline t2 tab t2 / t0 newline t3 tab t3 / t0 newline ] ] ] The second parameter N to CHARFREQ/TIMETEST can be left at 1 if you have a large enough file (or a slow enough CPU! ;-) -jn- -- --------------------------------------------------------------- There are two types of science: physics and stamp collecting! -- Sir Arthur Eddington joel-dot-neely-at-fedex-dot-com