Date: Sat, 30 Jan 1999 01:52:22 -0700 From: Warner Losh <imp@village.org> To: small@FreeBSD.ORG Subject: compressed executables in low memory environements Message-ID: <199901300852.BAA75275@harmony.village.org>
next in thread | raw e-mail | index | archive | help
Has any thought (or work) been given to being able to run compressed executables basically in place? Right now the gzip device in FreeBSD does almost this, but requires the entire program to be decompressed before running. What I had in mind would be something that would use fixed length blocks (not optimal for compression, but not bad either) so that they could be "paged" into uncompress memory easily? by way of example: If we had a compression scheme that gave 2:1 compression (including headers), then we could "page in" 256 bytes of compressed program text decompressing it to 512 bytes of text that the CPU could understand and execute. This would allow one to run in tight memory spots and squeeze out extra use from the machine. If the entire image were resident in ram/rom, this could be a big win. The wins become bigger as the compression ratio improves. However, there are lots of problems going down this path. Do you have a tool that compresses the executables so they still have reasonable headers for the OS, or does the OS do this behind everybody's back. I know that WinCE 2.0 and newer uses techniques like this to live in such a limited footprint. Just curious. My need for something like this is still far in the future, as there are many preliminaries to be done before I get to the state of needing this. Warner To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-small" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199901300852.BAA75275>