On Mon, Mar 4, 2013 at 7:04 AM, AJ Weber <aweber@comcast.net> wrote:
> Apologies for the tangential question, but how would pgpool2 "increase
> throughput"? Wouldn't the same number of statements be issued by your
> application? It would likely reduce the number of concurrent connections,
> but that doesn't necessarily equate to "increased throughput".
This is a pretty common subject. Most servers have a "peak
throughput" that occurs at some fixed number of connections. for
instance a common throughput graph of pgbench on a server might look
like this:
conns : tps
1 : 200
2 : 250
4 : 400
8 : 750
12 : 1200
16 : 2000
24 : 2200
28 : 2100
32 : 2000
40 : 1800
64 : 1200
80 : 800
100 : 400
So by concentrating your connections to be ~24 you would get maximum
throughput. Such a graph is typical for most db servers, just a
different "sweet spot" where the max throughput for a given number of
connections. Some servers fall off fast past this number, some just
slowly drop off.