The Uptime Infrastructure Monitor MySQL Advanced Metrics monitor collects the following performance metrics from a MySQL database:

MetricExplanation
UptimeThe number of seconds that MySQL has been running.
QuestionsThe number of queries that have been sent to the database.
Slow QueriesThe number of queries that take longer than long_query_time to complete.
Open TablesThe number of database tables that are opened independently by each concurrent thread.
QPSAThe average number of queries, per second, that must be exceeded before Uptime Infrastructure Monitor generates an alert.
Bytes ReceivedThe number of bytes received by the server.
Bytes SentThe number of bytes sent by the server to all clients.
Delayed Insert ThreadsThe number of delayed insert threads that must be exceeded before Uptime Infrastructure Monitor sends an alert.
Delayed ErrorsThe number of delayed insert threads that had an error.
Max Used ConnectionsThe maximum number of connections that have been in simultaneous use because the server was started.
Threads ConnectedThe maximum number of clients that can be connected to the database at any one time.
Threads RunningThe number of threads that are running, which can be used to determine whether or not the database is becoming overloaded.
QCache InsertsThe number of queries added to the query cache.
QCache HitsThe number of hits to the query cache (qcache_hits) to determine the number of query results taken directly from the cache instead of executing them.
QCache Lowmem PrunesThe number of QCache_lowmem_prunes that can be deleted from the cache because of low memory.
QCache Not CachedThe maximum number of queries that are not cached.
QCache Free MemoryThe amount of free memory for the query cache.
QCache Free BlocksThe number of free memory blocks in query cache.
QCache Table BlocksThe amount of query cache memory fragmentation.