[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
bug#17230: [PATCH 1/2] grep: may also use Boyer-Moore algorithm for case
From: |
Norihiro Tanaka |
Subject: |
bug#17230: [PATCH 1/2] grep: may also use Boyer-Moore algorithm for case-insensitive matching |
Date: |
Thu, 24 Apr 2014 08:59:38 +0900 |
Paul Eggert wrote:
> That's odd, as I'm not observing this slowdown.
Though I apply 17230.diff and tests, I don't observed slowdown. However,
I cann't find macros `BM_DELTA2_SEARCH' etc in 17230.diff. Could you also
consider them, and run (A) instead of (B)? It means that overheads by
`yes' and `head' should be ignored.
(A)
$ yes jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj | head -10000000 >k
$ grep -i jk
(B)
$ yes jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj | head -10000000 | grep -i jk
I attach the difference between current master and my version.
Though I don't analyze detail still, don't seem that overhead by check
for `trans' in `tr' function, which is called each time the comparison
of a character, can be ignorable.
Norihiro
17230.diff
Description: Text document