Selecting Hosts

Database Performance Monitor is designed to let you manage collections of servers together, and drill down into individual hosts as needed. For example, you can view Top Queries across all of your hosts, filter out some of them, or drill down to individual hosts.

The entire DPM web application operates on a set of hosts at once, and this set is controlled by the Host Filter in the top navigation bar. Type in the text field to do a full-text fuzzy-search against hosts. You can also click on an item in the dropdown menu.

Host Filter Expanded

While editing the Host Filter, you’ll see a hint to the right of the text field that you need to press Enter to apply the changes you’ve made.

The selected hosts are filtered by the currently selected time range. Hosts are included only if they are actively reporting data in the time range. We broaden the time range by an hour so that recently active hosts will not disappear immediately.

The Host Filter operates as a simple substring match by default. That is, if you type api into the Host Filter, any host whose name includes the substring api will become part of the set of active hosts. In the illustration above, api1 and api2 will be selected. However, webapp2 and webapp3 will not be selected, because they don’t contain the substring api. They are shown in the dropdown only as approximate matches, to help you select hosts more easily if you don’t know the exact names you are looking for.

The Host Filter is more than a simple substring match, however. It supports a more advanced selection syntax.

  • You can match hostnames exactly by wrapping them with the double quotes sign. The string "api2", for example, will match a host named api2 but not one named api20.
  • You can select hosts by their type (os, mysql, pgsql, redis and mongo at present), with syntax such as type=os or type=mysql.
  • You can also use Javascript’s regular expression syntax. The expression must start and end with /. For example, /webapp[5-7]/ will match webapp5 but not webapp2. This match is performed against the databases’s hostname only, and not the description.

Hosts can also optionally be tagged with custom labels from the Hosts List page. Once tagged, you can match all hosts with a given tag using the #tagname syntax. Tags cannot contain spaces or commas, but otherwise just about anything can be used for a tag name. For more information on applying tags to hosts, visit the documentation for the Inventory page.