Messages in this thread | ![/](/images/icornerl.gif) | | From | (Miquel van Smoorenburg) | Subject | Re: announce: ext2 compression patch | Date | Sat, 23 Mar 1996 20:29:18 +0100 (MET) |
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In article <9603221627.AA20799@gnu.mc.xerox.com>, Marty Leisner <leisner@sdsp.mc.xerox.com> wrote: > >I have to agree with Jerry Pournelle on this (he had a column a few >months ago in Byte where he talked about this). > >On the fly compression to writable file systems is a bad idea... >It encrypts your whole file system making recovery impossible...
It should be implemented differently; compression should be in a file-basis, not on a device-basis. This way, if a bit or byte falls over on your disk, it will just cause one (part of a) file to get corrupted.
For example, use a file system with 8K blocks. The file system should use 1K blocks internally. Compress every 8K block independently, and store the compressed 8K blocks in several 1K blocks.
I splitted bash in 8K blocks, and gzipped -9 every 8K block. The total nr. of blocks was 128, while the normal bash is 221 blocks. It's not to bad; gzip -9 on bash itself creates a bash.gz of 106 blocks.
Mike. -- + Miquel van Smoorenburg + Cistron Internet Services + Living is a | | miquels@cistron.nl (SP6) | Independent Dutch ISP | horizontal | + miquels@drinkel.ow.org + http://www.cistron.nl/ + fall +
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