October meeting recap

What a great meeting last night! Garlynn Woodsong gave us a tour of Urban Footprint, a scenario planning tool for development modeling. Fascinating! Did you know that “walkability” of a neighborhood can be determined by the number of intersections per square mile? And I learned a new term, “airshed” (like watershed, not bikeshed).

The fun really started at the end of his talk, when Garlynn mentioned “We’re having slow queries sometimes, what settings should we tune?” This sparked a lively discussion and resulted in probably our longest meeting ever. Matt Smiley gave us several tips on using top, iostat, and sar to troubleshoot.

Here’s the general procedure we came up with:
– Make sure you have monitoring configured correctly (including the pg activity log) and a decent baseline established. At a minimum: server CPU, memory, I/O, network, log slow queries.
– If you have other apps running on the db server, verify that it’s actually the db that’s causing the bottleneck.
– Back up your configs before you tinker with them; version control is advised.
– Start here: https://wiki.postgresql.org/wiki/Performance_Optimization with the first link: https://wiki.postgresql.org/wiki/Tuning_Your_PostgreSQL_Server

Thanks to Iovation for hosting us and providing pizza!

Next month, new member Eric Hanson’s going to talk about how he uses Postgres at Aquameta. See you then!