Re: Bound parameters on Linux are extremely slow (compared to unbound and/or Windows)

Humm... may be out of topic - if so, please forgive...

Are you sure that your Linux box is able to resolve network names?
Try to put all involved computers ip address in hosts file for both 
computers, and give a try.
I use Linux and Windows and the slowness network I detected has been 
related to name resolution.

Regards,

Edson


Em 25/05/2013 19:52, Reuven M. Lerner escreveu:
> Hi, everyone.  A project I'm assisting is connecting to PostgreSQL 
> (9.2) via JDBC.    We're experiencing extremely slow query execution, 
> for precisely the same queries, depending on (a) operating system and 
> (b) whether we use bind parameters.
>
> We're using two different Red Hat Linux systems (one running RHEL 5, 
> and the other RHEL 6).  The machines have 16 GB and 64 GB RAM, 
> respectively, with 4+ GB allocated to shared buffers on each one. 
> However, given that the performance difference is between psql and 
> JDBC, I doubt that these are significant factors.
>
> We have two different Java programs (which do 1,000 inserts), each of 
> which we've run 10 times on each of Windows and Linux.   The average 
> time needed for running each program is:
>
> Windows: 232 ms with binding, 152 ms without binding
> Linux: 2,233 ms (yes, 2.233 *seconds*) with binding, 176 ms without 
> binding
>
> We've also run the same 1,000 inserts via psql on a remote machine, 
> and the timing was quite fast (i.e., like what we saw on the Windows 
> machine).
>
> The combination of binding + Linux seems to be the problematic one 
> here, but I'm at a loss for why.
>
> I can provide the test programs if they'll help, but I'm first 
> wondering where the problem might lie.
>
> Any suggestions or ideas?  What additional information (e.g., the test 
> programs) would help to track this problem down?
>
> Thanks in advance,
>
> Reuven
>