Package: sed Version: 4.2.1-9 Severity: wishlist sed is inefficient on a regexp starting with "(.*":
$ time sed -n "s/\(.*49026\)/\1/p" ChangeLog 2012-01-12 23:39:18 (rev 49026, vinc17/xvii) 4.62s user 0.00s system 99% cpu 4.637 total Compare to the equivalent: $ time sed -n "s/^\(.*49026\)/\1/p" ChangeLog 2012-01-12 23:39:18 (rev 49026, vinc17/xvii) 0.27s user 0.00s system 99% cpu 0.278 total perl doesn't have this problem: $ time perl -ne "s/(.*49026)/\1/ and print" ChangeLog 2012-01-12 23:39:18 (rev 49026, vinc17/xvii) 0.08s user 0.00s system 98% cpu 0.081 total $ time perl -ne "s/^(.*49026)/\1/ and print" ChangeLog 2012-01-12 23:39:18 (rev 49026, vinc17/xvii) 0.06s user 0.01s system 94% cpu 0.076 total -- System Information: Debian Release: wheezy/sid APT prefers unstable APT policy: (500, 'unstable'), (500, 'testing'), (500, 'stable'), (1, 'experimental') Architecture: amd64 (x86_64) Kernel: Linux 3.2.0-1-amd64 (SMP w/2 CPU cores) Locale: LANG=POSIX, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8) Shell: /bin/sh linked to /bin/dash Versions of packages sed depends on: ii dpkg 1.16.1.2 ii install-info 4.13a.dfsg.1-8 ii libc6 2.13-24 ii libselinux1 2.1.0-4 sed recommends no packages. sed suggests no packages. -- no debconf information -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". Trouble? Contact [email protected]
