Filters

In OpenTSDB 2.2 tag key and value filters were introduced. This makes it easier to extract only the data that you want from storage. The filter framework is plugable to allow for tying into external systems such as asset management or provisioning systems.

Multiple filters on the same tag key are allowed and when processed, they are ANDed together e.g. if we have two filters host=literal_or(web01) and host=literal_or(web02) the query will always return empty. If two or more filters are included for the same tag key and one has group by enabled but another does not, then group by will effectively be true for all filters on that tag key.

Note that some type of filters may cause queries to execute slower than others, e.g. the regex and wildcard filters. Before fetching data from storage, the filters are processed to create a database filter based on UIDs so using the case sensitive "literal or" filter is always faster than regex because we can resolve the strings to UIDs and send those to the storage system for filtering. Instead if you ask for regex or wildcards with pre, post or infix filtering the TSD must retrieve all of the rows from storage with the tag key UID, then for each unique row, resolve the UIDs back to strings and then run the filter over the results. Also, filter sets with a large list of literals will be processed post storage to avoid creating a massive filter for the backing store to process. This limit defaults to 4096 and can be configured via the tsd.query.filter.expansion_limit parameter.

Built-in Filters

Plugins

As developers add plugins we will list them here.

To develop a plugin, simply extend the net.opentsdb.query.filter.TagVFilter class, create JAR per the Plugins documentation and drop it in your plugins directory. On start, the TSD will search for the plugin and load it. If there was an error with the implementation the TSD will not start up and will log the exception.