faster-gzip.patch

From jasonuhl@sgi.com Sat Feb 12 00:09:45 2005
Date: Sat, 12 Feb 2005 00:09:45 -0800
From: Jason Uhlenkott <jasonuhl@sgi.com>
To: Troy Heber <troy.heber@hp.com>
Cc: lkcd-devel@lists.sourceforge.net
Subject: [PATCH] Accelerate gzip dumps
Message-ID: <20050212080945.GA473110@dragonfly.engr.sgi.com>
References: <20050210221556.GN29315@me> <20050211104649.GA392879@dragonfly.engr.sgi.com> <20050211140731.GQ29315@me>
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As promised, this gives a big speed boost (~300% on a typical SGI
Altix) to gzip dumps, at only a marginal cost in dump size.

It also removes an incorrect comment (we don't fall back to RLE in the
indicated case).

Index: linux/drivers/dump/dump_gzip.c
===================================================================
--- linux.orig/drivers/dump/dump_gzip.c	2005-02-11 16:12:11.444284482 -0800
+++ linux/drivers/dump/dump_gzip.c	2005-02-11 16:32:28.535116151 -0800
@@ -48,8 +48,7 @@
 		 */
 		return(0);
 	}
-	if ((err = zlib_deflateInit(&dump_stream, Z_BEST_COMPRESSION)) != Z_OK) {
-		/* fall back to RLE compression */
+	if ((err = zlib_deflateInit(&dump_stream, Z_BEST_SPEED)) != Z_OK) {
 		printk("dump_compress_gzip(): zlib_deflateInit() "
 			"failed (%d)!\n", err);
 		return 0;