From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from plg.uwaterloo.ca ([129.97.140.10]) by hawkwind.utcs.toronto.edu with SMTP id <2748>; Fri, 9 Apr 1993 12:32:53 -0400 Received: by plg.uwaterloo.ca id <28706>; Fri, 9 Apr 1993 12:32:25 -0400 From: Dave Mason To: rc@hawkwind.utcs.toronto.edu In-reply-to: <93Apr8.203942edt.2538@groucho.cs.psu.edu> (message from Scott Schwartz on Thu, 8 Apr 1993 20:38:11 -0400) Subject: Speed of rc X-Face: %Q_F^9R-:'3MM7eZ6@E.x@f\*bgatzGv-8d%I~L[p^.F)3QF{kq\UTsu|e#?)3FPwJNvPPB !s*He|-*M^p*~bh"Nywm5NLL\\Rl3r(hWHY*F:$/RdKV*bS";n&#\Ov@*=]mu\}6tP Date: Fri, 9 Apr 1993 12:32:16 -0400 Of course it was 10 seconds after I finished reading (and deleting) John Mackin(sp?)'s note that I realized the problem: environment rc will have a significantly larger environment (rc functions) than sh, and many systems have *abysmal* exec performance because of the time spent copying the environment. I did some benchmarks on a MIPS M/120 (13 Specmarks) running RiscOS and a National Semiconductor 32016 (.75 Specmarks) running Sys5r2, and I don't remember the exact results, but execing with a 0K environment was about the expected factor of 20 faster on the MIPS, and with a 5K environment it was *much* slower - maybe a factor of only 4, and I calculated that in a research O/S we were working on (although it never ran so I couldn't verify this) the exec (with 5K environment) would run *faster* on the NS32016 than the existing one on the M/120. So, John: try a version of rc with an empty environment. I suspect the system times will be as fast as those for sh. ../Dave