[rt-users] Apache FastCGI and # of db connections

[Alex Vandiver]

On Fri, 2014-01-10 at 11:45 +0100, Václav Ovsík wrote:
> I have a question regarding behaviour of FastCGI processes and database
> connections. While preparing upgrade of RT 3.8.16 to RT 4.2.1 I noticed
> a change of FastCGI usage in the RT.

Thanks for bringing this to our attention.  This is a bug which affects
RT 4.0 and 4.2; the 4.0/fewer-active-handles branch resolves the issue.

> I did not study Plack too much - only look at
> http://search.cpan.org/~miyagawa/Plack-1.0030/lib/Plack/Handler/FCGI.pm
> and there is approach a bit different. One daemon is started standalone
> (forking to a number of processes) and Apache is configured to connect
> to this daemon
>  FastCgiExternalServer /tmp/myapp.fcgi -socket /tmp/fcgi.sock

This is a valid alternate deployment strategy, which comes with the
benefit that one can restart one RT server without affecting others, by
restarting its fastcgi process.  However, it requires additional system
configuration to ensure that these processes are started at server
startup time, and so forth, which is why this is not the deployment
suggested in RT's documentation, which we aim to keep as simple as
possible.

> Should I really increase PostgreSQL max_connections to 100 and don't
> bother with it?

Until a version of RT is released with the above branch, increasing the
max_connections is likely your best bet.  The additional connections
will consume some small amount of memory each, but this is likely
negligible, and will have no performance impact.
 - Alex