Rudder

We have a case where the displaying of rule page time increase enormously with the number of report in DB:

The metrics are as follow:

• number of nodes: ~75
• number of rules: ~45

(clearly not much)

And the timing for rule page:

• reports for ~12h (DB: 2Go) => 6s
• reports for ~24h (DB: 4Go) => 10s
• report for ~48h => 19s
• report for ~3 days => 35s
• report for ~4 days => 1m5s
• after, timeout of the server

Note that even for really few reports, the display time is already 6s!

Moreover, in that case, the database process seems to be CPU bounded, not I/O bounded: the i/o wait is almost 0, but CPU (when the page is rendering) is 100% for the postgres process.
The index are well touch (96%).
Java and Slapd do nothing during that time.
Other pages, like node list, are fast (in order of 1s) to display.

So:

• there seems to be a linear complexity somewhere in the query we are doing for rules.
• the index are well used, but they may be not sufficient