[naviserver-devel] ns_cache is still broken

[Zoran V. <zv...@ar...>]

Hi !

I got the same report from customers:

   timeout waiting for update: 59331.0.n.childs

We never use anything except ns_cache_create, ns_cache_flush
and ns_cache_eval commands.

This kind of error was happening much more often before and
I have tried to fix that bug some days ago. Aparently I found out
that due to the bug in cache.c, we always have expired the
cached entry and the ns_cache_eval was just re-caching it all
the time. This obviously exposed the problem more often
than now, as this bug is fixed. But, the "real" bug is still
lurking there. This means that if you do not use timed caches,
your program might get stucked in the cache code forever.
Again: this might not happen to you in million years but it can
happen the very next millisecond...
I cannot get any decent test to expose this bug, as this is
obviously some race condition in the code. I hope to be able
to get that working today, by reading the code and trying to
understand what it does. Please excuse me if I do some "non-optimal"
changes to get it working properly. At the moment, the correct
operation is paramount to us whereas speed/performance is not.

Cheers,
Zoran