There are 2 ways to do it. At a global VSE level and at individual VS level.
1, HTTP Live Invocation Timeout at a Global level
There is no separate property for HTTP Live invocation. There are properties applicable for all HTTP transactions and they are:
lisa.http.timeout.connection
lisa.http.timeout.socket
Pass these properties in local.properties
The value must be in milliseconds
Eg:
lisa.http.timeout.connection=30000
lisa.http.timeout.socket=5000
NOTE: The changes made here are applicable across all HTTP connections not just Live invocation alone
What is the difference between these 2 properties ?
The first property "lisa.http.timeout.connection" translates to Socket connection timeout. (java socket). This is the timeout in establishing the socket connection
The second property "lisa.http.timeout.socket" translates to SOTimeout on a socket. This is the timeout for receiving individual packets once the socket is established
Sotimeout vs Connectiontimeout (official response found on Java site)
A connection timeout is the maximum amount of time that the program is willing to wait to setup a connection to another process. You aren't getting or posting any application data at this point, just establishing the connection, itself. A socket timeout is the timeout when waiting for individual packets
2. HTTP Live Invocation Timeouts at Individual VS Level
Most often you dont want to set the timeouts at a global level and impact all the http connection. You want this to be very local to that specific VS that you deal with.
This can be achieved with the following mechanism:
Ultimately, you need to set 2 properties in the context of testExec and you could do that using Scriptable DPH in the listen step.