tmpfs panic

[Dmitry Morozovsky]

On Sun, 15 Jun 2008, Dmitry Morozovsky wrote:

DM> KB> > KB> I suspect this may be my mistake.
DM> KB> > KB> IN case you can reproduce it, please, try the patch below.
DM> KB> > 
DM> KB> > Well, it seems hard to reproduce, possibly some races in kernel memory 
DM> KB> > allocation exist. Keep trying (run rsync -aH svn tree to tmpfs in the loop)
DM> KB> 
DM> KB> Unmount is required to trigger the problem. Please, report to me whatever
DM> KB> your results are. I will commit the patch then.
DM> 
DM> yes, the loop contains rsync, umount, mount. I'll let this run for several 
DM> hours, then report back to you.

With about 80 turns without a panic I think it was great coincidence that I'd 
encountered this panic. ;-)

BTW, side result: 128M for kern.maxswzone is enough for filling tmpfs to 100% 
under amd64 with 4G RAM + 8G swap.

Also, I can observe tmpfs is doing non-optimal; I did not found straight ways 
to set block/frag size; I suppose for most tmpfs usage they should be decreases 
to the lowest values, such as 4k/512 -- what do you think?

Thanks!

Sincerely,
D.Marck                                     [DM5020, MCK-RIPE, DM3-RIPN]
[ FreeBSD committer:                                 marck at FreeBSD.org ]
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*** Dmitry Morozovsky --- D.Marck --- Wild Woozle --- marck at rinet.ru ***
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