SQL Server XTP Databases object
Applies to: 
SQL Server
The SQL Server XTP Databases performance object provides In-Memory OLTP database-specific counters.
Note
The SQL Server XTP Databases counters are not currently visible from sys.dm_os_performance_counters. On Windows, the counters can be viewed from System Monitor.
This table describes the SQL Server XTP Databases counters.
| Counter | Description |
|---|---|
| Avg Transaction Segment Large Data Size | Average size of transaction segment large data payload. This is a very low-level counter, not intended for customer use. |
| Avg Transaction Segment Size | Average size of transaction segment payload. If this value goes to zero, more pages are allocated from the backend allocator. This is a very low-level counter, not intended for customer use. |
| Flush Thread 256K Queue Depth | Flush Thread queue depth for 256K IO requests. |
| Flush Thread 4K Queue Depth | Flush Thread queue depth for 4K IO requests. |
| Flush Thread 64K Queue Depth | Flush Thread queue depth for 64K IO requests. |
| Flush Thread Frozen IOs/sec (256K) | The number of 256K IO requests encountered during flush page processing that are above the freeze threshold and thus cannot be issued. |
| Flush Thread Frozen IOs/sec (4K) | The number of 4K IO requests encountered during flush page processing that are above the freeze threshold and thus cannot be issued. |
| Flush Thread Frozen IOs/sec (64K) | The number of 64K IO requests encountered during flush page processing that are above the freeze threshold and thus cannot be issued. |
| IoPagePool256K Free List Count | Number of pages in the 256K IO page pool free list. If this value goes to zero, more pages are allocated from the backend allocator. This is a very low-level counter, not intended for customer use. |
| IoPagePool256K Total Allocated | Total number of pages allocated and held by the 256K IO page pool from the backend allocator. This is a very low-level counter, not intended for customer use. |
| IoPagePool4K Free List Count | Number of pages in the 4K IO page pool free list. If this value goes to zero, more pages are allocated from the backend allocator. This is a very low-level counter, not intended for customer use. |
| IoPagePool4K Total Allocated | Total number of pages allocated and held by the 4K IO page pool from the backend allocator. This is a very low-level counter, not intended for customer use. |
| IoPagePool64K Free List Count | Number of pages in the 64K IO page pool free list. If this value goes to zero, more pages are allocated from the backend allocator. This is a very low-level counter, not intended for customer use. |
| IoPagePool64K Total Allocated | Total number of pages allocated and held by the 64K IO page pool from the backend allocator. This is a very low-level counter, not intended for customer use. |
| MtLog 256K Expand Count | Number of times a 256K MtLog was expanded. This is a very low-level counter, not intended for customer use. |
| MtLog 256K IOs Outstanding | The number of outstanding 256K IO requests issued by MtLog. |
| MtLog 256K Page Fill %/Page Flushed | Average fill percentage of each 256K MtLog page flushed. This is a very low-level counter, not intended for customer use. |
| MtLog 256K Write Bytes/sec | Write bytes per second on 256K MtLog objects. This is a very low-level counter, not intended for customer use. |
| MtLog 4K Expand Count | Number of times a 4K MtLog was expanded. This is a very low-level counter, not intended for customer use. |
| MtLog 4K IOs Outstanding | The number of outstanding 4K IO requests issued by MtLog. |
| MtLog 4K Page Fill %/Page Flushed | Average fill percentage of each 4K MtLog page flushed. This is a very low-level counter, not intended for customer use. |
| MtLog 4K Write Bytes/sec | Write bytes per second on 4K MtLog objects. This is a very low-level counter, not intended for customer use. |
| MtLog 64K Expand Count | Number of times a 64K MtLog was expanded. This is a very low-level counter, not intended for customer use. |
| MtLog 64K IOs Outstanding | The number of outstanding 64K IO requests issued by MtLog. |
| MtLog 64K Page Fill %/Page Flushed | Average fill percentage of each 64K MtLog page flushed. This is a very low-level counter, not intended for customer use. |
| MtLog 64K Write Bytes/sec | Write bytes per second on 64K MtLog objects. This is a very low-level counter, not intended for customer use. |
| Num Merges | The number of merges in flight. |
| Num Merges/sec | The number of merges created per second (on average). |
| Num Serializations | The number of serializations in flight. |
| Num Serializations/sec | The number of serializations created per second (on average). |
| Redo Active Worker | The number of active redo workers. |
| Redo Log Processed Bytes/sec | Log bytes per second that Redo controller has processed. |
| Redo Segment Definition/Sec | The number segments definitions seen per second. This is a very low-level counter, not intended for customer use. |
| Tail Cache Page Count | Number of pages allocated in the Tail Cache. This is a very low-level counter, not intended for customer use. |
| Tail Cache Page Count Peak | Highest number of pages allocated in the Tail Cache. This is a very low-level counter, not intended for customer use. |