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Developers building applications on top of X will often want to record their own application-specific statistics. In X parlance, these are "User Defined App Stats".

See User Defined App Stats documentation for more information. 

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XVM Statistics

Where AEP Engine Statistics capture the statistics associated with a single AEP engine, Server Statistics pertain to the server itself (e.g. load average, memory usage, per-thread CPU utilization, object pools) and all applications/engines therein. Server stats are periodically collected and emitted packaged as Server Heartbeats that are modeled as ADM Messages. The server can:

• Log these heartbeat messages to a binary transaction log, then use tools like the Stats Dump Tool to query the log offline. 
• Trace heartbeats at varying levels of granularity, which is useful for debugging and performance tuning. 
• Emit the heartbeats to application registered handlers.
• Emit the heartbeats to connected Robin controllers. 

See the Server Statistics documentation for XVM Stats and Heartbeats documentation for more information.

Stats Dump Tool

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