Bug#513635: More on nscd and 100%

["Douglas E. Engert" <deengert@anl.gov>]

We too have seen this behavior with Ubuntu Hardy and Intrepid.
but may be seeing multiple problems.

using gdb to look at the striped nscd and libs, has not shown much,
other then accept fails because all the FD's (1024) have been allocated.

In one type of failure, nscd keeps working, but using 100% CPU.

A second type of failure looks like a deadlock in libnss-ldap, in
_nss_ldap_endpwent from _nss_compat_getpwname_r where all 32 worker
threads are waiting for the same lock.

We now have a non-striped version of nscd and libnss-ldap running
waiting for the next problem to use gdb to see what is going on.


Comment on nscd:

It looks like nscd will accept requests (i.e. each using a FD)
and queue them for the worker threads until it runs out of FD's,
rather then not accepting new requests. It makes no allowance for
the fact the worker threads may also need to open files or sockets
too.

--

 Douglas E. Engert  <DEEngert@anl.gov>
 Argonne National Laboratory
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