Re: slow pg_connect()

firerox(at)centrum(dot)cz wrote:
> It takes more then 0.05s :(
>
> Only this function reduce server speed max to 20request per second.
>
If you need that sort of frequent database access, you might want to
look into:

- Doing more work in each connection and reducing the number of
connections required;
- Using multiple connections in parallel;
- Pooling connections so you don't need to create a new one for every job;
- Using a more efficient database connector and/or language;
- Dispatching requests to a persistent database access provider that's
always connected

However, your connections are indeed taking a long time. I wrote a
trivial test using psycopg for Python and found that the following script:

#!/usr/bin/env python
import psycopg
conn = pyscopg.connect("dbname=testdb")

generally took 0.035 seconds (350ms) to run on my workstation -
including OS process creation, Python interpreter startup, database
interface loading, connection, disconnection, and process termination.

A quick timing test shows that the connection/disconnection can be
performed 100 times in 1.2 seconds:

import psycopg
import timeit
print timeit.Timer('conn = psycopg.connect("dbname=craig")', 'import
psycopg').timeit(number=100);

... and this is still with an interpreted language. I wouldn't be too
surprised if much better again could be achieved with the C/C++ APIs,
though I don't currently feel the desire to write a test for that.

--
Craig Ringer