[Pgpool-hackers] Admin interface, statistics views, etc

[Guillaume Lelarge]

Hi,

I've been thinking about the new release. I've always wanted to add
something in pgAdmin that could discover the "pgpool" server. There are
two ways to do it: with a "SHOW pool_status", and with the
inet_server_addr() stored function. There should be a third in 9.1 with
the pg_stat_get_backend_server_port() stored function.

I would like to see two kinds of informations: configuration (which we
already have with the "SHOW pool_status" statement), and statistics
(which, AFAICT, aren't available). It would be great to have something
like pg_stat_activity but at the pgpool level. I mean, the
pg_stat_activity stat view only display the IP address of the pgpool
server. So, it would be great to know where the real client is.
Something like:

SELECT * FROM pool_stat_activity;

-[ RECORD 1 ]----+--------------------------------
pool_pid         |
pool_id          |
pool_start       |
pgsql_hostname   | 127.0.0.1
pgsql_port       | 5432
pgsql_pid        |
working          | f

pool_pid would be the PID of the pgPool child connected to the real
client. pool_id would by the pool number (connectionid could be a better
name). pool_start would be the timestamp wrt to the start of pgPool
child process. pgsql_hostname, pgsql_port would identify the PostgreSQL
server it is connected to. pgsql_pid would be the PID of the postgres
backend process (this information would help to cross the information
with pg_stat_activity). working would be a boolean value telling which
pool_id is really working at the moment.

There could be other interesting informations as the list of servers
(pool_stat_servers) which could tell us how many servers are available,
which one are really available, how many queries were executed on each, etc.

Seems it would be a great project to add to the 3.0 release, don't you
think?

Other comments?


-- 
Guillaume
 http://www.postgresql.fr
 http://dalibo.com