These messages are harmless by themselves, as they just indicate the
number of unused dentries was getting too big. Maybe they're triggered
by whatever caused the swapping?
> When I reboot, I see a *lot* of lines like:
>
> try_to_unuse: didn't find entry %8lx
>
> scroll up the screen, but are not stored in the syslogs. These come
> from mm/swapfile.c.
This one is interesting, as it could indicate that the system is losing
track of which pages are swapped. (Maybe that's why it asked for your
second swapfile?)
I just reposted a patch that may have some bearing on this -- could you
give it a test?
Regards,
Bill