ASPerf
ASPerf is an example that demonstrates how to perform timing measurements to calculate how long it takes ActiveSpaces to perform an action.
ASPerf consists of a master and any number of slaves. The master is used to remotely invoke methods on the slaves. Each remote invocation method on a slave times the action being performed and the timings are returned in the results of the remote invocation. The master then displays the results returned from each of the slaves.
The ASPerf example uses two different spaces:
| ASPerfCtrl | Used by the master to remotely invoke methods on the slaves. |
| ASPerfShared | Used by all of the remote invocation methods of the slaves for performing the actions of the remote invocation methods, such as putting data into the space. |
Additionally, each slave creates its own individual space, which the slave can use instead of using the ASPerfShared space that it shares with all of the other slaves. Remote invocations from the master indicate which space a slave should use. In this way, you can see the timing differences between when a slave uses its own local space or uses the shared space in its remote invocation methods.
The ASPerf master creates the ASPerfCtrl space and then joins it as a leech. Each slave joins the ASPerfCtrl space as a seeder. In this way, the ASPerf master can use remote invocation on all seeders to invoke the same remote invocation method on all of the slaves of the ASPerfCtrl space.
ASPerf slaves can join the ASPerfShared space or their own local space as seeders or leeches.
Whether a slave joins these spaces as a leech or a seeder is controlled by the command line options of the ASPerf slave. The minimum number of seeders required for the ASPerfShared space and the ASPerf slave's own space is one. So if an ASPerf slave is started as a leech, an as-agent must also be run so that the slave's own space will have a seeder.
Since an as-agent joins all spaces in a metaspace as a seeder, when the ASPerf master tries to remotely invoke a method on all seeders of the ASPerfCtrl space, the remote invocation is also be tried on the as-agent. Since the as-agent does not know about the ASPerf remote invocation methods, as-agent reports an error back to the ASPerf master. For this reason, a special version of as-agent, ASPerfAgent, is provided with the ASPerf example.
Similar to as-agent, ASPerfAgent joins spaces in a metaspace as a seeder and thereby lends its computing resources to the space. However, ASPerfAgent specifically does not join the ASPerfCtrl space. So when the ASPerf master does remote invocations on all seeders of the ASPerfCtrl space, the remote invocation is not be tried on the ASPerfAgent and unnecessary errors are not reported back to the master.