pt-query-digest, Anemometer or “Anemomaster” do a great job of analysing your queries and giving you visibility into what’s going on with your MySQL servers. However, the place where the query digests are written is just some MySQL tables on some server. Do you have monitoring/alerts on that table? How will you verify a specific query does not exceed some runtime/execution count threshold, and get notified when it does?
At Outbrain we use Graphite to collect almost all of our data. We like it for its simplicity and for the fact it has a “push” strategy as opposed to “pull” strategy: every service/server/collectd writes (pushes) its own data to Graphite, as opposed to having some centralized monitoring service trying to pull data from thousands of servers & services. We also have a great Graphite dashboard (developed at our company by Erez Mazor) called graphitus, which is a very sophisticated and easily configurable visualization solution (see documentation).
Our love/hate relationship with Nagios boil down to having a single Nagios plugin: one that reads data from Graphite. We use Nagios to generate our alerts, and dream of the day we will substitute it with something else (there’s not too much love in this love/hate relationship).
Graphite is a numeric timeseries data monitoring solution. How do you throw MySQL query analysis into Graphite, then?
The answer lies within the flexible structure of a Graphite metric entry, which is a freely composed path, such as collectd.hosts.us-east.myhost01.mysql.gauge-Threads_running.value. Graphite does not require you to pre-define paths, and you can use anything that makes sense to you. Thus, you can use a slow query’s text, for example, as part of the Graphite entry path. This is not entirely simple as the graphite path limits the allowed characters. So this is what we do: Continue reading » “Monitoring DML/slow queries with graphite”