Re: announce: ext2 compression patch

Mon, 1 Apr 1996 21:58:01 +0200 (MET DST)

Just my two cents about this file system question....

When I was still using msdos, some years ago, I occasionnaly used a freeware
disk compressor, named JAM. It had a really cool feature : it had several
packing algorithms, so most of the time I used the FAST one, that allowed
me to accelerate my hard disk access times, and then when I wanted to
take a coffee-break, I launched a disk optimizer, that repacked all the
recent data with a better packing algorithm - this was quite fast, because
it only tried to repack the recent data that was still using the fast

I think this could be a great feature for those who run linux on
low-power computers. perhaps the repack phase could be lauched in the night
with a crontab program, or by a daemon when the load is low.

"Encrypting the filesystem" is not a real issue for me - if the compressed
filesystem packs only a few disk sectors at a time. this way, if a disk
sector gets destroyed, the damage won't be much higher that at the present
time - for example if a directory is destructed, only the few more entryes
that fitted in this sector because of compression would be destroyed.

The next step could even be to use part of the data space gained with
compression, to fit a few percents of redundary error correction data - in
order to recover in case of a disk failure.

Just my two cents - too bad that I don't code better ;-)

Michel "Walken" LESPINASSE - Student at Ecole Centrale Paris (France)
www PC demo coder & official LiGNUx support
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