captureTransactionLatencyStats

Property that can be used to control the default sampling size for series stats.If the number of datapoints collected in a stats interval exceeds this size, the computation for histographical data will be lossy. Increasing the value reduces loss of datapoints, but results in greater overhead in stats collection in terms of both memory usage and pressure on the process caches.enables collection of latency stats as messages flow through the AEP engine's transaction processing machinery.

captureEventLatencyStats

Property that globally enables collection of message latency stats as messages flow through the system. These statistics include latencies in the flow outside of transaction processing. For received messages these statistics include transmission, deserialization and dispatch costs. For sent messages these include serialization and transmission costs.

When set to true, timings for messages are captured as they flow through the system. Enablement of these stats is required to collect message bus latency stats. Enabling this property can increase latency due to the overhead of tracking timestamps.

captureMessageTypeStats

Property that enables tracking of message statistics on a per message type basis.

When set to true, timings for each message type are individually tracked as separate stats

Due to their overhead, these statistics are not included in heartbeats emitted by an XVM.

messageTypeStatsLatenciesToCapture

Property that enables tracking of latency statistics on a per message type babasis

Property controlling which latency stats on a per message type basis. This property is specified as a comma separated list of values. Valid value include:

• all Indicates that all available per message type latency stats should be collected.
• none Indicates that no message type latency stats should be collected.
• c2o Indicates create to offer latencies should be captured.
• o2p Indicates offer to poll (input queueing time) should be captured.
• mfilt Indicates that time spent in application message filters should be captured.
• mpproc Indicates that time spent in the engine prior to message dispatch should be captured.
• mproc Indicates that the time spent in application message handlers should be captured.

The values 'all' or 'none' may not be combined with other values.

This value only applies when captureMessageTypeStats is true. When not specified the value defaults to all.

See Also:

• ISrvMonAppEngineStats for details on general engine stats.
• ISrvMonMsgTypeStats for details on stats collected on a per message type basis.
• AepEngineDescriptor.html.setMessageTypeStatsLatenciesToCapture(String) for programmatic configuration
• DDL Reference - for configuration settings.

capturePerTransactionStats

perTransactionStatsLogging

Configuration

See Per Transaction Stats for more details.

Time spent in AepEngine.sendMessage().

The time in the AepEngine's send call. This latency will be a subset of mproc for solicited sends and it includes msendc.

Time spent in the AepEngine's core send logic.

This leg includes enqueuing the message for delivery in the corresponding bus manager.

Time spent from the point where transaction commit is started to send or store commit, whichever occurs first.

This latency measures the time taken in any bookkeeping done by the engine prior to commit the transaction to store (or for an engine without a store until outbound messages are released for delivery).

The send commit latency: i.e. time from when send commit is initiated, to receipt of send completion event.

This latency represents the time from when outbound messages for a transaction are released to the time that all acknowledgements for the messages are received.

Because this latency includes acknowledgement time a high value for csend does not necessarily indicate that downstream latency will be affected. The Message Latencies listed below allow this value to be decomposied further.

Time spent from the point the store commit completes to the beginning of the send commit which releases a transaction's outbound messages for delivery.

If the engine doesn't have a store, then this statistic is not captured as messages are released immediately.

The store commit latency i.e. time from when store commit is initiated to receipt of store completion event.

This latency includes the time spent serializing transaction contents, persisting to the store's transaction log, inter cluster replication, and replication to backup members including the replication ack.

High values in cstore will impact downstream message latencies because store commit must complete before outbound messages are released for delivery. The cstore latency is further broken down in the Store Latencies listed below.

Records latencies for the first transaction processing leg.

Transaction Leg One includes time spent from the point where the first message of a transaction is received to submission of send/store commit. It includes message processing and and any overhead associated with transactional book keeping done by the engine.

Each transaction leg is a portion of the overall commit time that is processed on the Aep Engine's thread. The sum of the transaction leg stats are important in that they determine the overall throughput that an application can sustain in terms of transactions per second.

tleg2

Records latencies for the second transaction processing leg.

Transaction Leg Two includes time spent from the point where the send/store commit completion is received to the submission of store/send commit.

Each transaction leg is a portion of the overall commit time that is processed on the Aep Engine's thread. The sum of the transaction leg stats are important in that they determine the overall throughput that an application can sustain in terms of transactions per second.

Records latencies for the third transaction processing leg.

Transaction Leg Three includes time spent from the point where the store/store commit completion is received to the completion of the transaction commit.

Each transaction leg is a portion of the overall commit time that is processed on the Aep Engine's thread. The sum of the transaction leg stats are important in that they determine the overall throughput that an application can sustain in terms of transactions per second.

Records latencies for receipt of a message to transmission of the last outbound message.

The create to send latencies in microseconds, the time in microseconds from message creation to when send was called for it.

Note, this statistic is for outbound messages sent through a bus and is different from the c2o statistic captured for an AepEngine which tracks the create to offer times for received/injected messages offered to the application's input queue.

The send to serialize latencies in microseconds, the time from when the message was sent until it was serialized in preparation for transmission on the wire.

For an engine with a store this will include the time from the application's send call, the replication hop (if there is a store) and time through the bus manager's disruptor if detached commit is enabled for the bus manager.

The time spent on the wire from when the message was written to the wire by the sender to the time it was received off the wire by the receiver.

Note: that this metric is subject to clock skew when the sending and receiving sides are on different hosts.

The time from when the serialized form was received from the wire to deserialization.

Additional time spent by the engine dispatching the message to the application handler is covered by mpproc (see the Transaction Latencies table).

The origin to receive latencies in microseconds.

The time from when a message was originally created to when it was received by the binding.

The wire to wire latencies in microseconds, for outbound messages the time from when the corresponding inbound message was received off the wire to when the outbound message was written to the wire.