Apama 10.15.0 | Connecting Apama Applications to External Components | Standard Connectivity Plug-ins | The HTTP Client Transport Connectivity Plug-in | Monitoring status for the HTTP client
 
Monitoring status for the HTTP client
The HTTP client component provides status values via the user status mechanism. It provides the following metrics (where prefix consists of the chain identifier and plug-in name, typically HTTPClientChain.HTTPClientTransport):
Key
Description
prefix.status
FAILED if the most recent request has failed, otherwise ONLINE.
prefix.errorsTowardsHost
Number of error responses to requests which have been sent.
prefix.responsesTowardsHost
Number of success responses to requests which have been sent.
prefix.requestLatencyEWMAShortMillis
A quickly-evolving exponentially-weighted moving average of request latencies, in milliseconds.
prefix.requestLatencyEWMALongMillis
A longer-term exponentially-weighted moving average of request latencies, in milliseconds.
prefix.requestSizeEWMAShortBytes
A quickly-evolving exponentially-weighted moving average of request sizes, in bytes.
prefix.requestSizeEWMALongBytes
A longer-term exponentially-weighted moving average of request sizes, in bytes.
prefix.requestSizeMaxInLastHourBytes
The maximum request size in bytes since the start of the last 1 hour measurement period.
prefix.responseSizeEWMAShortBytes
A quickly-evolving exponentially-weighted moving average of response sizes, in bytes.
prefix.responseSizeEWMALongBytes
A longer-term exponentially-weighted moving average of response sizes, in bytes.
prefix.responseSizeMaxInLastHourBytes
The maximum response size in bytes since the start of the last 1 hour measurement period.
prefix.numClients
Number of configured clients.
prefix.serializedRequests
Number of requests received with metadata.concurrencyControlFlush set and evaluated to true.
prefix.concurrencyUtilizationPercent
A percentage representing how fully the capacity of the number of clients is being used. 0 if only one client is being used. 100 if all clients are being used. If the transport throughput is too low and this metric is also low, see Executing HTTP requests concurrently for information on how to tune your data for better performance.
prefix.queueSize
The current size of the client request queue in the HTTP transport.
For each request/response that is processed, the above MaxInLastHour values are updated if either of the following conditions is true:
*The size of the current message is greater than the existing maximum.
*The existing maximum value was set more than 1 hour ago.
Error responses are not included in the response size metrics. The request size metrics are calculated before compression and the response size metrics are calculated after decompression.
For more information about monitor status information published by the correlator, see Managing and Monitoring over REST and Watching correlator runtime status.
When using Software AG Command Central to manage your correlator, see also Monitoring the KPIs for EPL applications and connectivity plug-ins.
Note: 
Command Central integration is deprecated and will be removed in a later release.