Some performance issues (since everybody is testing ... :)

Hi there,

I am starting with the conclusions to spare time:
- persistent connections invention stands somewhere between the fire and the
wheel
- unix sockets is not much compared to tcpip (at least on my Linux 2.0.30
box).
- parsing and executing a trivial "select 17;" accounts for a lot of time,
someone wanted hints on what is critical, profiler statistics coroborated.

Stressing postmaster with 100 connections
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Connection type Time (seconds)
----------------------------------------------------
tcpip local 15
tcpip local with select 26
unix sockets 15
unix sockets with select 26
tcpip local persistent 0
tcpip local persistent with select 2
unix sockets persistent 0
unix sockets persistent with select 2

Stressing postmaster with 2000 persistent connections
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Connection type Time (seconds)
-----------------------------------------------------
tcpip local 3
tcpip local with select 45
unix sockets 3
unix sockets with select 45

NOTES:
- tests were (repeatedly!) run via php3 as apache module
- scrips attached, comments wellcome
- "with select" below means a pg_Exec("select 17;")
inserted between Connect and Close

.co.

Costin Oproiu ---------------- http://www2.deuroconsult.ro/~co
Ciprian Porumbescu 10, ap.13 tel/fax: +(40)-68-183528
Brasov 2200, ROMANIA email: co(at)deuroconsult(dot)ro
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