Reduce DB connection pool partition count
Reduce DB connection pool partition count

We defaulted to creating 5 partitions in our connection pooling code.
Partitions are useful only inasmuch as they reduce lock contention when
attempting to acquire a new connection. Even in high-throughput
environments, we are never bottlenecked on connection acquisition.

By defaulting to 1 partition, we reduce the number of bookkeeping
threads required. Each partition requires 5 bookkeeping threads, so by
reducing the partition count to 1 we eliminate 20 threads, and save
about 20M of resident memory on users systems.

Signed-off-by: Deepak Giridharagopal <d11186354d1ef01ca06ae37d7e23e827da13e85f@puppetlabs.com>

melissa/puppetdb,shrug/puppetdb,grimradical/puppetdb,johnduarte/puppetdb,puppetlabs/puppetdb,grimradical/puppetdb,shrug/puppetdb,waynr/puppetdb,puppetlabs/puppetdb,melissa/puppetdb,johnduarte/puppetdb,senior/puppetdb,kbrezina/puppetdb,highb/puppetdb,shrug/puppetdb,rbrw/puppetdb,grimradical/puppetdb,highb/puppetdb,kbarber/puppetdb,mullr/puppetdb,cprice404/puppetdb,puppetlabs/puppetdb,rbrw/puppetdb,kbarber/puppetdb,mullr/puppetdb,senior/puppetdb,puppetlabs/puppetdb,github/puppetlabs-puppetdb,highb/puppetdb,nfagerlund/puppetdb,rbrw/puppetdb,jantman/puppetdb,johnduarte/puppetdb,github/puppetlabs-puppetdb,wkalt/puppetdb,waynr/puppetdb,nfagerlund/puppetdb,ajroetker/puppetdb,senior/puppetdb,senior/puppetdb,puppetlabs/puppetdb,ajroetker/puppetdb,cprice404/puppetdb,mullr/puppetdb,kbarber/puppetdb,github/puppetlabs-puppetdb,melissa/puppetdb,wkalt/puppetdb,shrug/puppetdb,mullr/puppetdb,kbrezina/puppetdb,wkalt/puppetdb,waynr/puppetdb,rbrw/puppetdb,waynr/puppetdb,ajroetker/puppetdb,kbarber/puppetdb,wkalt/puppetdb,mullr/puppetdb,rbrw/puppetdb,jantman/puppetdb,grimradical/puppetdb,ajroetker/puppetdb,jantman/puppetdb,kbrezina/puppetdb,johnduarte/puppetdb,highb/puppetdb,kbrezina/puppetdb,nfagerlund/puppetdb,cprice404/puppetdb