SSAS 2019 Tabular Processing Issue

Question

Issue Summary:
We are experiencing intermittent failures while processing a SQL Server Analysis Services (SSAS) 2019 Tabular model.

Environment:

Microsoft SQL Server 2019 (RTM-CU32-GDR) (KB5102335) 15.0.4480.2 (X64)
Enterprise Edition: Core-based Licensing (64-bit)
Windows Server 2019 Standard
Build 17763
Running in a virtualized environment (Hypervisor)

Problem Description:

During the execution of Process Full operations on individual partitions through SSIS and manually, processing occasionally becomes stuck indefinitely.
The SSIS package or SSMS remains in a running state waiting for the Analysis Services command to complete and does not receive either a success or failure response from SSAS.

The following errors have been identified in the SSAS Flight Recorder trace:

"The request was cancelled because the connection was closed."

and

"Internal Error Code: 0xC11C001B"

The issue is intermittent and does not consistently occur on the same table or partition.

Observed Behavior:

The error occurs during partition processing in a Tabular model.
The affected processing operation never completes successfully.
The SSIS package remains waiting indefinitely for the processing command to return.
The SSMS remains waiting indefinitely for the processing command to return.
The issue can occur on different tables and partitions.
No correlation has been identified with a specific table, partition, or dataset.
The issue appears random and is difficult to reproduce consistently.

Evidence Collected:

The Flight Recorder trace shows a failure associated with a processing command:

"Command End"
for an XMLA request similar to:

XML
true
<Refresh>
...
</Refresh>
</Batch>

After that, the following error is recorded:

The request was cancelled because the connection was closed.
along with:
Internal Error Code: 0xC11C001B

Troubleshooting Performed:

1. Version Validation

The SSAS instance has been updated to:

SQL Server 2019 CU32-GDR
Version 15.0.4480.2

2. Concurrency Investigation

We verified that there are no concurrent processing operations against the same Tabular model.
Although multiple SSIS packages may be running in the environment simultaneously, we have not identified multiple packages processing the same Tabular database at the time of failure.

3. Memory Configuration Review

Current SSAS memory settings:

XML
<VertiPaqMemoryLimit>90</VertiPaqMemoryLimit>
<TotalMemoryLimit>80</TotalMemoryLimit>
<LowMemoryLimit>65</LowMemoryLimit>

No clear evidence of memory pressure has been identified in association with the failures.

Additional Information:

Processing is initiated through SSIS.
The SSIS package does not fail, instead, it remains running indefinitely while waiting for the SSAS processing command to finish.
The failure is only visible in SSAS traces and Flight Recorder logs.
The issue affects multiple tables and partitions rather than a single object.

We would appreciate Microsoft's assistance in:

Determining the root cause of the internal error: 0xC11C001B

Understanding why processing enters a state where:

Flight Recorder records an internal error.
The connection is reported as closed.
The processing operation never completes properly.
SSIS continues waiting indefinitely for a response.

Thank you for your assistance. We would appreciate guidance on any additional data collection required to support root cause analysis.