---
title: "SQL Server XTP Garbage Collection | Microsoft Docs"
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ms.date: "03/14/2017"
ms.prod: sql
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---
# SQL Server XTP Garbage Collection
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  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.|  
  
## See Also  
 [SQL Server XTP (In-Memory OLTP) Performance Counters](../../relational-databases/performance-monitor/sql-server-xtp-in-memory-oltp-performance-counters.md)