(ITS#8702) SLAPD_MAX_DAEMON_THREADS is too small

[hyc@openldap.org]

Full_Name: Howard Chu
Version: HEAD
OS: Solaris 11.3
URL: ftp://ftp.openldap.org/incoming/
Submission from: (NULL) (31.216.236.133)
Submitted by: hyc


Was benchmarking on an Oracle M8 box with 2048 SPARC VCPUs. With 1024 slapd
threads configured, we needed 64 listener threads and 64 threadqueues to
eliminate slapd bottlenecks, but the current default in daemon.c only allows up
to 16 listener threads.

It's a #ifndef so easily overridable at compile time, but 16 is probably too
small in this age of processors with more and more cores.