Keepalive and HTTP Concurrent Connections
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Keepalive and HTTP Concurrent Connections


Article ID: 232681


Updated On:


CA API Gateway


I have two questions - 

1) Keepalive - 
As per the below documentation, we have a setting on the HTTP listener port to change the keepalive timeout (keepAliveTimeout= <new value in milliseconds> ). Is this setting only for version 9.4? I don't see this setting in the documentation for version 10.0 and version 10.1. 

I tried setting this advanced property keepAliveTimeout on a listen port in version 9.4 to 2000ms. However I still the TCP connections left open for almost 60secs.

2) HTTP Concurrency - 
I see this advanced Listener port concurrencyWarningThreshold property to enable the logging when the limit is exceeded. Is there any such parameter to generate log when the HTTP Concurrency is exceeded on the global level?



Release :

Component :



Yes the setting do apply to the later releases same configuration as Gateway 9.4 keepalive  for listing port: advanced properties 


The settings are advanced third party configuration of tomcat It was removed from the later docs but can still be used (tomcat), 


All the tomcat connector properties should be able to be used as advanced properties of the gateway listener, maybe it's 3rd party info..   Link to the tomcat for more info on them



The number of milliseconds this Connector will wait for another HTTP request before closing the connection. The default value is to use the value that has been set for the connectionTimeout attribute. Use a value of -1 to indicate no (i.e. infinite) timeout.



The maximum number of HTTP requests which can be pipelined until the connection is closed by the server. Setting this attribute to 1 will disable HTTP/1.0 keep-alive, as well as HTTP/1.1 keep-alive and pipelining. Setting this to -1 will allow an unlimited amount of pipelined or keep-alive HTTP requests. If not specified, this attribute is set to 100.

HTTP Concurrency 

request.http.concurrency will provide the current threads in use 

From the documentation there is a paragraph on usage:

However, threads processing at a high rate is difficult to capture.  Determining the correct values for your Gateway's concurrency requires a certain amount of trial and error.