Date: Thu, 01 Nov 2007 01:05:54 +0100 From: Eduardo Morras <nec556@retena.com> To: freebsd-hackers@freebsd.org Subject: memory pool, rfc Message-ID: <4727D3B2000A88A6@> (added by postmaster@resmaa07.ono.com)
next in thread | raw e-mail | index | archive | help
Hello:
I have some free time and want to do an memory pool. The idea is
to have a memory zone of N KB (or several MB) compressed in memory. I
have fast compression algorithms now that can release under BSD
licence that are faster than hd i/o, so it take less
compress/decompress a memory zone than read/write it to disk. I don't
know if it already exist for FreeBSD, so if it's already done i'll
try to improve it.
- Each memory chunk is compressed separately, so i can decompress and
use one without decompress anyother one.
- In 4KB chunks of text i get 50-60 % compression (avg 2 - 1.6 KB result)
- In 4KB chunks of binary (application code) i get 30-40 %
compression (avg 2.8 - 2.4 KB result)
- In both cases, results may vary depending on data type and chunk
size, greater implies better compression
- Speed once implemented will be very fast. Current speed hogs a PATA 133 disk.
For what can be used?
- Memory pools in applications (like malloc)
- Ram disks
- Disk Cache (permit bigger disk cache)
- 'On the fly' filesystem compression (and it takes less read/write
compressed data than non-compressed)
- Perhaps add it as Virtual Memory swap cache?
- Other
Don't point me to zlib or libbzip2, they are on another league and
are much slower than my code.
Thanks
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4727D3B2000A88A6>