What does an internal connection that's named INT: Exchange

[reimer_pods]

At a client's site the users are experiencing performance problems, with no explnation up to now. Checking the connection I found several internal connections with the name "INT: Exchange".

Does anyone know, what those connections are supposed to do?

Environment: SA 12.0.1.3537 on Windows 2K8R2

EDIT: I've found another post, stating that this should be short lived connection created by intra-query parallelism. But those connection seem to be sticky and won't disappear.

[Breck_Carter]

FYI INT:EXCHANGE connections can legitimately persist for hours if the query takes a long time to run. I have seen many examples of problems caused by intra-query parallelism over the years but none has ever been explained by incorrect "stickiness"... not to me, anyway.

[former_SQLA_member1694878 · Accepted solution]

But those connection seem to be sticky and won't disappear.

This is a known bug in some versions of SQL Anywhere. The issue can be resolved by updating to 12.0.1.4060 or later.

The same issue is also fixed in 11.0.1.3040, 16.0.0.1802 and all versions of 17.

Disabling intra-query parallelism with max_query_tasks=1 can be used to temporarily avoid the issue if needed.