PR/9308 CVS commit: src/usr.bin/sort

[David Laight <dsl%netbsd.org@localhost>]

The following reply was made to PR kern/9308; it has been noted by GNATS.

From: David Laight <dsl%netbsd.org@localhost>
To: gnats-bugs%gnats.NetBSD.org@localhost
Cc: 
Subject: PR/9308 CVS commit: src/usr.bin/sort
Date: Tue, 18 Aug 2009 18:00:28 +0000

 Module Name:   src
 Committed By:  dsl
 Date:          Tue Aug 18 18:00:28 UTC 2009
 
 Modified Files:
        src/usr.bin/sort: append.c files.c fsort.c sort.c sort.h
 
 Log Message:
 The code that attempted to sort large files by sorting each chunk by the
 first key byte and writing to a temp file, then sorting the records from
 each temp file that had the same first key byte (and repeating for upto
 4 key bytes) was a nice idea, but completely doomed to failure.
 Eg PR/9308 where a 70MB file has all but one record the same and short keys.
 Not only does the code not work, it is rather guaranteed to be slow.
 Instead always use a merge sort for fully sorted chunk of records (each
 temporary file contains one lot of sorted records).
 The -H option already did this, so just rip out all the code and variables
 that can't be used when -H was specified.
 Further cleanup to come ...
 
 
 To generate a diff of this commit:
 cvs rdiff -u -r1.17 -r1.18 src/usr.bin/sort/append.c
 cvs rdiff -u -r1.33 -r1.34 src/usr.bin/sort/files.c
 cvs rdiff -u -r1.36 -r1.37 src/usr.bin/sort/fsort.c
 cvs rdiff -u -r1.49 -r1.50 src/usr.bin/sort/sort.c
 cvs rdiff -u -r1.22 -r1.23 src/usr.bin/sort/sort.h
 
 Please note that diffs are not public domain; they are subject to the
 copyright notices on the relevant files.