From owner-freebsd-current Sat Nov 11 19:41:29 1995 Return-Path: owner-current Received: (from root@localhost) by freefall.freebsd.org (8.6.12/8.6.6) id TAA20675 for current-outgoing; Sat, 11 Nov 1995 19:41:29 -0800 Received: from hutcs.cs.hut.fi (root@hutcs.cs.hut.fi [130.233.192.2]) by freefall.freebsd.org (8.6.12/8.6.6) with SMTP id TAA20661 for ; Sat, 11 Nov 1995 19:41:24 -0800 Received: from shadows.cs.hut.fi by hutcs.cs.hut.fi with SMTP id AA14453 (5.65c8/HUTCS-S 1.4 for ); Sun, 12 Nov 1995 05:41:19 +0200 Received: (hsu@localhost) by shadows.cs.hut.fi (8.6.10/8.6.10) id FAA08651; Sun, 12 Nov 1995 05:41:34 +0200 Date: Sun, 12 Nov 1995 05:41:34 +0200 Message-Id: <199511120341.FAA08651@shadows.cs.hut.fi> From: Heikki Suonsivu To: michael butler Cc: freebsd-current@freefall.FreeBSD.org In-Reply-To: michael butler's message of 11 Nov 1995 13:06:34 +0200 Subject: Re: cvs commit: src/usr.sbin/pppd RELNOTES Sender: owner-current@FreeBSD.org Precedence: bulk > Has anyone looked at it, if it could be modified to do zip compression ZIP is computationally expensive .. you'll speed most of your time in the Huh? hsu#hauki.clinet.fi Sun 37: time gzip -1 < csh > /dev/null real 0:00.60; user 0.582; system 0.031; cpu 101.6%; swaps 0; disk reads 0; disk writes 0; average size 687; max size 192 hsu#hauki.clinet.fi Sun 38: time gzip -1 < csh > /dev/null real 0:00.60; user 0.578; system 0.038; cpu 100.0%; swaps 0; disk reads 0; disk writes 0; average size 718; max size 192 hsu#hauki.clinet.fi Sun 39: time gzip -1 < csh > /dev/null real 0:00.61; user 0.583; system 0.031; cpu 100.0%; swaps 0; disk reads 0; disk writes 0; average size 706; max size 192 hsu#hauki.clinet.fi Sun 40: time gzip -1 < csh > /dev/null real 0:00.60; user 0.579; system 0.038; cpu 100.0%; swaps 0; disk reads 0; disk writes 0; average size 718; max size 192 So its about 0.6s hsu#hauki.clinet.fi Sun 41: time compress < csh > /dev/null real 0:00.75; user 0.644; system 0.070; cpu 94.6%; swaps 0; disk reads 5; disk writes 0; average size 741; max size 450 hsu#hauki.clinet.fi Sun 42: time compress < csh > /dev/null real 0:00.73; user 0.662; system 0.038; cpu 94.5%; swaps 0; disk reads 0; disk writes 0; average size 763; max size 450 hsu#hauki.clinet.fi Sun 43: time compress < csh > /dev/null real 0:00.67; user 0.651; system 0.038; cpu 101.4%; swaps 0; disk reads 0; disk writes 0; average size 757; max size 450 hsu#hauki.clinet.fi Sun 44: time compress < csh > /dev/null real 0:00.71; user 0.699; system 0.031; cpu 101.4%; swaps 0; disk reads 0; disk writes 0; average size 756; max size 450 compress -b16 takes more, 0.65s, but as predictor-1 uses only 15 bits: hsu#hauki.clinet.fi Sun 45: time compress -b15 < csh > /dev/null real 0:00.52; user 0.502; system 0.031; cpu 101.9%; swaps 0; disk reads 0; disk writes 0; average size 737; max size 450 hsu#hauki.clinet.fi Sun 46: time compress -b15 < csh > /dev/null real 0:00.53; user 0.481; system 0.054; cpu 100.0%; swaps 0; disk reads 0; disk writes 0; average size 761; max size 450 hsu#hauki.clinet.fi Sun 47: time compress -b15 < csh > /dev/null real 0:00.53; user 0.476; system 0.053; cpu 98.1%; swaps 0; disk reads 0; disk writes 0; average size 787; max size 450 hsu#hauki.clinet.fi Sun 48: time compress -b15 < csh > /dev/null real 0:00.54; user 0.506; system 0.022; cpu 96.2%; swaps 0; disk reads 0; disk writes 0; average size 795; max size 450 hsu#hauki.clinet.fi Sun 49: time compress -b15 < csh > /tmp/csh.Z real 0:00.60; user 0.464; system 0.106; cpu 93.3%; swaps 0; disk reads 0; disk writes 6; average size 784; max size 446 compress -b15 wins by 20-30%, 0.5s But lets look at decompression times! hsu#hauki.clinet.fi Sun 50: time gzip -1 < csh > /tmp/csh.gz real 0:00.78; user 0.571; system 0.064; cpu 80.7%; swaps 0; disk reads 0; disk writes 5; average size 705; max size 192 hsu#hauki.clinet.fi Sun 51: time compress -d < /tmp/csh.Z > /dev/null real 0:00.34; user 0.302; system 0.046; cpu 100.0%; swaps 0; disk reads 0; disk writes 0; average size 770; max size 452 hsu#hauki.clinet.fi Sun 52: time compress -d < /tmp/csh.Z > /dev/null real 0:00.34; user 0.334; system 0.015; cpu 100.0%; swaps 0; disk reads 0; disk writes 0; average size 749; max size 452 hsu#hauki.clinet.fi Sun 53: time compress -d < /tmp/csh.Z > /dev/null real 0:00.33; user 0.322; system 0.023; cpu 103.0%; swaps 0; disk reads 0; disk writes 0; average size 750; max size 452 hsu#hauki.clinet.fi Sun 54: time compress -d < /tmp/csh.Z > /dev/null real 0:00.33; user 0.293; system 0.045; cpu 100.0%; swaps 0; disk reads 0; disk writes 0; average size 794; max size 452 compress -d takes 0.3s. hsu#hauki.clinet.fi Sun 55: time gzip -d < /tmp/csh.gz > /dev/null real 0:00.19; user 0.172; system 0.030; cpu 105.2%; swaps 0; disk reads 0; disk writes 0; average size 800; max size 178 hsu#hauki.clinet.fi Sun 56: time gzip -d < /tmp/csh.gz > /dev/null real 0:00.19; user 0.192; system 0.015; cpu 105.2%; swaps 0; disk reads 0; disk writes 0; average size 773; max size 162 hsu#hauki.clinet.fi Sun 57: time gzip -d < /tmp/csh.gz > /dev/null real 0:00.19; user 0.184; system 0.024; cpu 105.2%; swaps 0; disk reads 0; disk writes 0; average size 750; max size 150 hsu#hauki.clinet.fi Sun 58: time gzip -d < /tmp/csh.gz > /dev/null real 0:00.20; user 0.178; system 0.032; cpu 100.0%; swaps 0; disk reads 0; disk writes 0; average size 738; max size 138 gzip -d takes 0.2s. compress -b15 0.5s + 0.3s = 0.8s gzip -1 0.6s + 0.2s = 0.8s I can't see any difference, except in the file sizes: hsu#hauki.clinet.fi Sun 59: ls -l /tmp/csh.{Z,gz} -rw------- 1 root bin 170735 Nov 12 05:16 /tmp/csh.Z -rw------- 1 root bin 138760 Nov 12 05:16 /tmp/csh.gz This was on a P90, -current from two weeks back. Disclaimer: csh doesn't necessarily represent "standard data pattern on TCP/IP links" :-). -- Heikki Suonsivu, T{ysikuu 10 C 83/02210 Espoo/FINLAND, hsu@cs.hut.fi home +358-0-8031121 work -4513377 fax -4555276 riippu SN