Re: A little speed up for awk
:Hoi,
:
:We now use the one true awk in DragonFly BSD as our default.
:Some people reported poor performance in some cases and, while
:looking over the source, i noticed a cheap speed improvement.
:Maybe you like it.
:
:Thx,
:Andy
Well, that's a fine little patch but I really doubt it will
make much of a dent in awk's performance.
If you really want to have a go at tracking down potential
performance issues I recommend first doing some side-by-side
comparisons between the old and new awk and then compiling
up the new awk with profiling (-pg) and seeing if there is
anything obvious in the profile output that could be fixed.
The issue is likely to be algorithmic in nature.
-Matt
Matthew Dillon
<dillon@backplane.com>
:Index: tran.c
:===================================================================
:RCS file: /home/dcvs/src/contrib/awk20040207/tran.c,v
:retrieving revision 1.1.1.1
:diff -u -p -r1.1.1.1 tran.c
:--- tran.c 17 Apr 2004 19:41:31 -0000 1.1.1.1
:+++ tran.c 1 Nov 2004 19:05:26 -0000
:@@ -396,11 +396,13 @@ char *getpssval(Cell *vp) /* get str
: char *tostring(const char *s) /* make a copy of string s */
: {
: char *p;
:+ size_t size;
:
:- p = (char *) malloc(strlen(s)+1);
:+ size = strlen(s) + 1;
:+ p = (char *) malloc(size);
: if (p == NULL)
: FATAL("out of space in tostring on %s", s);
:- strcpy(p, s);
:+ bcopy(s, p, size);
: return(p);
: }
討論串 (同標題文章)
完整討論串 (本文為第 2 之 7 篇)：