X-Authentication-Warning:	delorie.com: mail set sender to djgpp-bounces using -f
NNTP-Posting-Date:	Thu, 01 Nov 2007 21:08:08 -0500
Message-ID:	<472A8686.4080500@zytor.com>
Date:	Thu, 01 Nov 2007 19:08:06 -0700
From:	"H. Peter Anvin" <hpa AT zytor DOT com>
User-Agent:	Thunderbird 2.0.0.5 (X11/20070727)
MIME-Version:	1.0
Newsgroups:	comp.os.msdos.djgpp
CC:	Robert Riebisch <Robert DOT Riebisch AT arcor DOT de>
Subject:	Re: Why "upx --brute" might be a bad idea...
References:	<4728e78c$0$16659$9b4e6d93 AT newsspool3 DOT arcor-online DOT net> <472A847C DOT 8030008 AT zytor DOT com>
In-Reply-To:	<472A847C.8030008@zytor.com>
Lines:	26
X-Usenet-Provider:	http://www.giganews.com
NNTP-Posting-Host:	67.169.144.158
X-Trace:	sv3-S6VPZXdiXDYk4hfx6YIwja2PtaiTZeDB4rNalCm0DnPB8aiDBrNoG5AMBDQTlHIQcqcAUukQYoP6Sco!T/0LpF4jAmftk2ZxwzrXEGKOhiwFIHfifgma6Ku5WPyJ3jDMq8Ysl2ANXoYNSJN9zdMSbwPeJjZt!+8KWV3I=
X-Complaints-To:	abuse AT comcast DOT net
X-DMCA-Complaints-To:	dmca AT comcast DOT net
X-Abuse-and-DMCA-Info:	Please be sure to forward a copy of ALL headers
X-Abuse-and-DMCA-Info:	Otherwise we will be unable to process your complaint properly
X-Postfilter:	1.3.36
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp
Reply-To:	djgpp AT delorie DOT com

H. Peter Anvin wrote:
> Robert Riebisch wrote:
>> Hi!
>>
>> Please read this thread at
>> <http://www.bttr-software.de/forum/forum_entry.php?id=1220>, how UPXed
>> binaries cause compile slowdowns.
>>
> 
> "upx --brute" and "upx --ultra-brute" runs a bunch of algorithms, and 
> picks the smallest one, which may or may not be LZMA.  I don't know how 
> they affect decompression speed, and it would be interesting to find out.
> 
> In particular, the NASM build robot 
> (ftp://ftp.zytor.com/pub/nasm/snapshots/) appear to generate marginally 
> smaller binaries with --[ultra-]brute than with --lzma --best, and I'm 
> wondering where the difference comes from.  It would also be nice to 
> know what algorithm it ends up using so I can tell it to use the same 
> one every time, instead of trying them all every time taking time (a 
> whopping minute every night ;)
> 

Just found upx --lzma --best --all-filters which generate the same 
output as --[ultra-]brute.

	-hpa

- Raw text -