9.3.5-P1 now issues "socket: too many open file descriptors"

Ed Ravin eravin at panix.com
Thu Jul 10 13:54:11 UTC 2008


I have two caching name servers with identical configurations and more or
less identical usage patterns.  One of them is still running 9.3.4-P1.  It
has 22 file descriptors in use at the moment.  The file descriptor use
does not seem to fluctuate.

The other one is running 9.3.5-P1.  When I installed it, it immediately
went to 256 file descriptors in use and began issuing this error:

    socket: too many open file descriptors

After some research, I read about FD_SETSIZE defaulting to 256 and
recompiled with

    -DFD_SETSIZE=512

It is curently using between 320 and 377 file descriptors, and still
sometimes peaks over 512 and issues the error above.

This is big difference in resource consumption - is this related to
the security fix?  Is this intentional?

What's the impact when named has too many file descriptors open?  Do
queries get dropped?


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