Re: PostgreSQL->JDBC->Tomcat->Apache resource uses

Hi,
I have a set up where we use just that which you describe. We have the
addition of having some heavy duty server software populatining the database
continually. User access the results via apache->tomcat->jdbc->postgres.

In our backend software we keep two persistant connections to the DB for all
read/write activity (one for each), which result in separate OS processes
for each. From the web interface, there are several, but as each connection
is for often single queries, not many connections (or processes) ever build
up. The better way to do it from tomcat is to set up a connection pool,
that way you can keep connection amounts down, so that you dont overload the
db server.

Our set up is postgres and on java server reader/writer app on a Sun Netra
X1, with 40Gb space, and 512mb memory. Tomcat and apache are on another Sun
Netra X1 machine. We have had no problems yet, and the database is getting
bigger all the time.

In our test environment though we did encounter problems if we ran all the
componants on a single machine with 128 Mb of physical memory. We kept
getting IO delays as each processes was reading/writing to swap (I think)
which made the system unusable after a while, as the IO wait was pushing 80%
most of the time. As soon as we stopped any particular process, and less
swap space was required the problem was diminished.

Hope that helps

Nikk Anderson

-----Original Message-----
From: Nick Fankhauser [mailto:nickf(at)ontko(dot)com]
Sent: 13 November 2001 19:56
To: Psql-Jdbc; pgsql-admin
Subject: PostgreSQL->JDBC->Tomcat->Apache resource uses

And finally, if anyone else is running PostgreSQL->JDBC->Tomcat->Apache, I'm
curious about your hardware configuration & experiences with it. Any
mistakes that you can help me avoid?

Thanks everyone!

-Nick

--------------------------------------------------------------------------
Nick Fankhauser nickf(at)ontko(dot)com Phone 1.765.935.4283 Fax 1.765.962.9788
Ray Ontko & Co. Software Consulting Services http://www.ontko.com/