RTSDK/EMA receives only RefreshMsg with no UpdateMsg - RFA 7.x gets streaming from same service

data271828

We're migrating from RFA 7.x to RTSDK/EMA (C++) and encountering an issue where we receive only initial RefreshMsg (snapshots) but no subsequent UpdateMsg (streaming updates) during active market hours.
Configuration:
* API: RTSDK (EMA C++)
* Service: hEDD
* Domain: marketPrice (MMT_MARKET_PRICE)
* Symbols: 4
* Field View: 8 fields (BID=22
Code:
```
req_msg.serviceName("hEDD")
.name("AAPL.O") // example
.interestAfterRefresh(true) // Explicitly request streaming
.payload(/* field view */);
```
What we've verified:
1. Using .interestAfterRefresh(true) to request streaming (not snapshot-only)
2. Service directory query shows hEDD supports "RealTime/TickByTick" QoS
3. RefreshMsg arrives successfully for all symbols with StreamState::OpenEnum and DataState::OkEnum
4. onUpdateMsg() callback is implemented and logged (never fires)
5. Testing during active market hours with ultra-high-volume symbols
Our legacy RFA 7.x handlers using the SAME account credentials and SAME service (hEDD) with InterestAfterRefresh = true DO receive streaming UpdateMsg successfully. They've been running in production for years with thousands of updates per second.
```
// RFA 7.x configuration (works fine):
rfa::sessionLayer::OMMItemIntSpec intSpec;
intSpec.setInterestAfterRefresh(true);
intSpec.setServiceName("hEDD");
// ... receives streaming updates continuously
```
Questions:
1. Are there known behavioral differences between RFA 7.x and RTSDK/EMA when connecting to hEDD service?
2. Does hEDD require additional subscription parameters in RTSDK/EMA that weren't needed in RFA 7.x?
3. Could there be account-level settings that enable streaming for RFA but not RTSDK/EMA?
4. Is there a migration guide covering RFA→RTSDK behavioral differences with hEDD specifically?
Any insights would be greatly appreciated. Since RFA works but EMA doesn't with identical configuration

Jirapongse

@data271828

Thank you for reaching out to us.

Regarding the real-time streaming services, there are no different between RFA and EMA. Both APIs can retrieve real-time streaming data from the real-time services.

There are a lot of examples in the RTSDK (EMA) package. It is better to test the services with those examples.

The first example could be the 100_MP_Streaming sample. Please try this example to confirm that you can retrieve streaming data from the real‑time services. You can use AAPL.O when the market is open, or use forex RICs such as JPY=.

Please note that the example runs for 60 seconds. If you need it to run longer, you can add a sleep call inside the while loop to extend the runtime. This example uses the API’s dispatch mode, so the main thread must sleep to allow the dispatch loop to run and process incoming events.

int main( int argc, char* argv[] )

{ 

	try { 

		AppClient client;

		OmmConsumer consumer( OmmConsumerConfig().host( "localhost:14002" ).username( "user" ) );

		consumer.registerClient( ReqMsg().serviceName( "DIRECT_FEED" ).name( "IBM.N" ), client );


		while(true)
                                       sleep( 60000 );				// API calls onRefreshMsg(), onUpdateMsg(), or onStatusMsg()

	} catch ( const OmmException& excp ) {

		cout << excp << endl;

	}

	return 0;

}

You also need to change the server, username, service name, and item name.

For the View example, please refer to the 360_MP_View example. For the user's dispatch mode, please refer to the 130_MP_UserDisp example.

Moreover, you need to enable the trace log in the EMA to check the incoming and outgoing messages by using the XmlTraceToFile configuration (EmaConfig.xml) in the Consumer. For other trace configurations, please refer to the EMA Configuration Guide. For example:

	<ConsumerList>
		<Consumer>
			<Name value="Consumer_1"/>
			<Channel value="Channel_1"/>
			<Logger value="Logger_1"/>
			<Dictionary value="Dictionary_1"/>
			<XmlTraceToFile value="1"/>
                                   </Consumer>

…

Then, the EMA trace file will be created. Please share this trace file.