I previously explained how to get one-minute resolution in Munin. The process to get sub-minute resolution in Munin is more tricky. The main reason it’s more tricky is that cron only runs once per minute, which means data must be generated and cached in between cron runs for collection when cron runs. In the case where a single datapoint is collected each time cron runs, the time at which cron runs is sufficient to store the data in rrd. With multiple datapoints being collected on a single cron run, it’s necessary to embed......
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I’ve recently been conducting some performance testing of a PaaS solution. In an effot to capture specific details resulting from these performance tests and how the test systems hold up under load, I looked into a few monitoring tools. Munin caught my eye as being easy to setup and having a large set of data available out of the box. The plugin architecture also made it attractive. One major drawback to Munin was the five minute resolution. During performance tests, it’s necessary to capture data much more frequently. With the latest Munin, it’s......
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Munin is a monitoring tool which captures and graphs system data, such as CPU utilization, load and I/O. Munin is designed so that all data is collected by plugins. This means that every built in graph is a plugin that was included with the Munin distribution. Each plugin adheres to the interface (not a literal OO inteface), as shown below. Munin uses Round Robin Database files (.rrd) to store captured data. The default time configuration in Munin collects data in five minute increments. Some important details: Plugins can be written in any language,......
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