Reloads with Data Gateway are randomly slower, sometimes they last for 3 hours until they are automatically aborted.
The same reloads usually run faster and they can be completed in the right time if relaunched manually or automatically.
The logs do not show specific error messages.
Resolution
We recommend two actions to resolve the problem.
The first is to activate the process isolation in order to reduce the number of reloads running at the same time. Please, follow this article.
It is possible to start with a value of 10 for the ODBC|SAPBW|SAPSQL_MAX_PROCESS_COUNT parameter and adjust it after some tests.
The second action is to add the "DISCONNECT" command after every query and to start every new query with a "LIB CONNECT".
This will force the closure and re-creation of the connection every time it is needed.
More information about the DISCONNECT statement can be found here.
We always recommend to keep Data Gateway on the latest version available.
Cause
This intermittent problem can be due to different causes.
In many cases the system can't handle multiple connections efficiently and this can lead to severe slowness in the data connection. Activating a Process Isolation will help to avoid this.
It is also possible that there is a delay between the connection opening and the query.
A connection for a query can be opened at the beginning a reload, then kept open for a while and re-called later for another table load in the script.
It is possible that there is a disconnection when the connection is not working. This can happen if another connection to the same location is called by a concurrent reload or if a timeout automatically closes the connection.
It is possible to force Data Gateway to recreate the connection using the "DISCONNECT" statement in the script.
Environment
- Qlik Data Gateway all supported versions.
