Re: Connections per second?

Alejandro Fernandez <ale@e-group.org> writes:

> Hi,
> 
> I'm writing a small but must-be-fast cgi program that for each hit
> it gets, it reads an indexed table in a postgres database and writes
> a log to a file based on the result. Any idea how many hits a second
> I can get to before things start crashing, or queuing up too much,
> etc? And will postgres be one of the first to fall? Do any of you
> think it can handle 2000 hits a second (what I think I could get at
> peak times) - and what would it need to do so? Persistent
> connections? Are there any examples or old threads on writing a
> similar program in C with libpq?

Doing it as CGI is going to have two big performance penalties:

1) Kernel and system overhead for starting of a new process per hit,
   plus interpreter startup if you're using a scripting language
2) Overhead in Postgres for creating a database connection from scratch

Doing it in C will only eliminate the interpreter startup.

You really want a non-CGI solution (such as mod_perl) and you really
want persistent connections (Apache::DBI is one solution that works
with mod_perl).  Java servlets with a connection pooling library would
also work.

-Doug