EMA API Performance improvement

Thank you for reaching out to us.

You can check the Real-Time SDKs Performance Test Summary article that summarizes the performance report.

You can also refer to the EMA PerfTools in the package which demonstrate best practice and coding for performance.

The key point is that, in the EMA callback methods (such as onUpdateMsg), the application must return as fast as possible. The application can clone retrieved messages and then put them into queues so the messages can be processed by other threads. Therefore, a dispatching thread is freed to dispatch next incoming messages.

Otherwise, the application can use the horizontal scaling by creating multiple OMM Consumer instances. You can refer to the Horizontal Scaling example in the API package.

@Jirapongse

Thank you for your prompt response.
We checked the links you have shared and have made some changes in our EmaConfig.xml file but there has not been a significant improvement in performance.
Right now, we are facing slowness in EMA API while sending subscription requests to TREP server. So, for example, currently with RFA API code in production, we are able to send 30k requests to TREP server but with EMA API this number is only 10k.
So, I wanted to understand that with EMA API, will subsequent requests be sent to/processed by TREP server only when the response of already sent requests is completely processed at our end?

According to this discussion, there is no request throttle in EMA. This means that all requests registered by application will directly be sent to server. Moreover, the watchlist size used to generate the performance report is 100,000 items so 30k items should be okay in EMA.

You may run the EMA PerfTools in the package to verify the number of subcribed items. The PerfTools are uses to generate the performance report.

Are you using EMA C++, Java, or C#?

We are using Java.

I modified the ex100_MP_Streaming example to subcribe to 30k items from the simulated service and found that it can retrieve all 30k refresh messages.

{

		OmmConsumer consumer = null;


		try

		{

			AppClient appClient = new AppClient();


			OmmConsumerConfig config = EmaFactory.createOmmConsumerConfig();


			consumer  = EmaFactory.createOmmConsumer(config.host("127.0.0.1:14002").username("user"));



			ReqMsg reqMsg = EmaFactory.createReqMsg();
for(int i=1;i<=30000;i++) {

			

				consumer.registerClient(reqMsg.serviceName("DIRECT_FEED").name("PTT"+i+".BK"), appClient);

			}



			while(true)

				Thread.sleep(60000);			

		}

You may try modify the simple example to subscribe to 30k items and then check if it can retrieve all responses.

Hi @Jirapongse,

Thanks for your prompt response.
In the above example, you are connecting to DIRECT_FEED service but in our application we are connecting to ADS services and our service name is IDN_SELECTFEED. Can you please provide an example relevant to that for benchmarking? Also, what is the expected response time for lets say 30k items?

Hi,

We tried to delegate all the retrieved messages to a thread pool in Java so that all the messages can be read and processed in a separate thread but in this approach we are not able to read the payload in msg object and our getting NullPointerException. Can you please provide an example to clone the retrieved message and process it in a separate thread?