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DateWed, 12 Oct 2005 11:09:45 +0200
FromPavel Machek <>
SubjectRe: Linux Kernel Dump Summit 2005
Digg This
Hi!

CMD | NET TIME (in seconds) | OUTPUT SIZE (in bytes) ---------+--------------------------------+------------------------ cp | 35.94 (usr 0.23, sys 14.16) | 2,121,438,352 (100.0%) lzf | 54.30 (usr 35.04, sys 13.10) | 1,959,473,330 ( 92.3%) gzip -1 | 200.36 (usr 186.84, sys 11.73) | 1,938,686,487 ( 91.3%) ---------+--------------------------------+------------------------
Although it is too early to say lzf's compress ratio is good enough, its compression speed is impressive indeed.

As you say, the speed of lzf relative to gzip is impressive.
However if the properties of the kernel dump mean that it is not suitable for compression then surely it is not efficient to spend any time on it.
And the
result also suggests that it is too early to give up the idea of full dump with compression.

Are you sure? :-)
If we are talking about systems with 32GB of memory then we must be taking about organisations who can afford an extra 100GB of disk space just for keeping their kernel dump files.

I would expect that speed of recovery would always be the primary concern. Would you agree?

Notice that suspend2 project actually introduced compression *for speed*. Doing it right means that it is faster to do it compressed. See Jamie Lokier's description how to *never* slow down.
Pavel
-- 
if you have sharp zaurus hardware you don't need... you know my address
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