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Re: JFFS min_free_size
Your mail isn't getting through to me because your mailserver is broken.
Having a broken mailserver is not an excuse for responding to private
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On Fri, 16 Mar 2001, Stephen Brasher wrote:
> My question is, what is a reasonable fmc->min_free_size?
Good question. The code in question currently reads...
1 sector, obviously.
+ 1 x max_chunk_size, for when a nodes overlaps the end of a sector
+ 1 x max_chunk_size again, which ought to be enough to handle
the case where a rename causes a name to grow, and GC has
to write out larger nodes than the ones it's obsoleting.
We should fix it so it doesn't have to write the name
_every_ time. Later.
+ another 2 sectors because people keep getting GC stuck and
we don't know why. This scares me - I want formal proof
of correctness of whatever number we put here. dwmw2.
fmc->min_free_size = fmc->sector_size << 2;
Theoretically, we should only require 2 * sector_size. In practice, that
sometimes wasn't enough, and we didn't reproduce the problem in-house so
didn't find out why, and I increased it to 4 * sector_size just to be on
the safe side.
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