SQL Server XTP Garbage Collection object
Applies to: 
SQL Server
The SQL Server XTP Garbage Collection performance object contains counters related to the In-Memory OLTP engine's garbage collector.
This table describes the SQL Server XTP Garbage Collection counters.
| Counter | Description |
|---|---|
| Dusty corner scan retries/sec (GC-issued) | The number of scan retries due to write conflicts during dusty corner sweeps issued by the garbage collector (on average), per second. This is a very low-level counter, not intended for customer use. |
| Main GC work items/sec | The number of work items processed by the main GC thread. |
| Parallel GC work item/sec | The number of times a parallel thread has executed a GC work item. |
| Rows processed/sec | The number of rows processed by the garbage collector (on average), per second. |
| Rows processed/sec (first in bucket and removed) | The number of rows processed by the garbage collector that were first in the corresponding hash bucket, and were able to be removed immediately (on average), per second. |
| Rows processed/sec (first in bucket) | The number of rows processed by the garbage collector that were first in the corresponding hash bucket (on average), per second. |
| Rows processed/sec (marked for unlink) | The number of rows processed by the garbage collector that were already marked for unlink (on average), per second. |
| Rows processed/sec (no sweep needed) | The number of rows processed by the garbage collector that will not require a dusty corner sweep (on average), per second. |
| Sweep expired rows removed/sec | The number of expired rows removed during dusty corner sweeps (on average), per second. |
| Sweep expired rows touched/sec | The number of expired rows touched during dusty corner sweeps (on average), per second. |
| Sweep expiring rows touched/sec | The number of expiring rows touched during dusty corner sweeps (on average), per second. |
| Sweep rows touched/sec | The number of rows touched during dusty corner sweeps (on average), per second. |
| Sweep scans started/sec | The number of dusty corner sweep scans started (on average), per second. |
Example
You begin to explore the query performance counters in this object using this T-SQL query on the sys.dm_os_performance_counters dynamic management view:
SELECT * FROM sys.dm_os_performance_counters
WHERE object_name LIKE '%XTP Garbage Collection%';