This plugin adds support for pt-heartbeat monitoring when running pt-table-checksum and pt-online-schema-change.
First, configure the pt-plugin-heartbeat.pm file and specify the heartbeat table (default is percona.heartbeat).
Then run either pt-online-schema-change or pt-table-checksum with --plugin='pt-plugin-heartbeat.pm' option.
This requires Percona Toolkit 2.2.8 or newer.