Memory-Optimized Tables

Monitor Memory Optimized Table Space Usage :

;
WITH    system_allocated_memory ( system_allocated_memory_in_mb )
          AS ( SELECT   ISNULL(( SELECT CONVERT(DECIMAL(18, 2), ( SUM(TMS.memory_allocated_for_table_kb)
                                                              + SUM(TMS.memory_allocated_for_indexes_kb) )
                                        / 1024.00)
                                 FROM   [sys].[dm_db_xtp_table_memory_stats] TMS
                                 WHERE  TMS.object_id <= 0
                               ), 0.00)
             ),
        table_index_memory ( table_used_memory_in_mb, table_unused_memory_in_mb, index_used_memory_in_mb, index_unused_memory_in_mb )
          AS ( SELECT   ISNULL(( SELECT CONVERT(DECIMAL(18, 2), ( SUM(TMS.memory_used_by_table_kb)
                                                              / 1024.00 ))
                               ), 0.00) AS table_used_memory_in_mb ,
                        ISNULL(( SELECT CONVERT(DECIMAL(18, 2), ( SUM(TMS.memory_allocated_for_table_kb)
                                                              - SUM(TMS.memory_used_by_table_kb) )
                                        / 1024.00)
                               ), 0.00) AS table_unused_memory_in_mb ,
                        ISNULL(( SELECT CONVERT(DECIMAL(18, 2), ( SUM(TMS.memory_used_by_indexes_kb)
                                                              / 1024.00 ))
                               ), 0.00) AS index_used_memory_in_mb ,
                        ISNULL(( SELECT CONVERT(DECIMAL(18, 2), ( SUM(TMS.memory_allocated_for_indexes_kb)
                                                              - SUM(TMS.memory_used_by_indexes_kb) )
                                        / 1024.00)
                               ), 0.00) AS index_unused_memory_in_mb
               FROM     [sys].[dm_db_xtp_table_memory_stats] TMS
               WHERE    TMS.object_id > 0
             )
    SELECT  s.system_allocated_memory_in_mb ,
            t.table_used_memory_in_mb ,
            t.table_unused_memory_in_mb ,
            t.index_used_memory_in_mb ,
            t.index_unused_memory_in_mb ,
            ISNULL(( SELECT DATABASEPROPERTYEX(DB_NAME(DB_ID()),
                                               'IsXTPSupported')
                   ), 0) AS has_memory_optimized_filegroup
    FROM    system_allocated_memory s ,
            table_index_memory t

SELECT  t.object_id ,
        t.name ,
        ISNULL(( SELECT CONVERT(DECIMAL(18, 2), ( TMS.memory_used_by_table_kb )
                        / 1024.00)
               ), 0.00) AS table_used_memory_in_mb ,
        ISNULL(( SELECT CONVERT(DECIMAL(18, 2), ( TMS.memory_allocated_for_table_kb
                                                  - TMS.memory_used_by_table_kb )
                        / 1024.00)
               ), 0.00) AS table_unused_memory_in_mb ,
        ISNULL(( SELECT CONVERT(DECIMAL(18, 2), ( TMS.memory_used_by_indexes_kb )
                        / 1024.00)
               ), 0.00) AS index_used_memory_in_mb ,
        ISNULL(( SELECT CONVERT(DECIMAL(18, 2), ( TMS.memory_allocated_for_indexes_kb
                                                  - TMS.memory_used_by_indexes_kb )
                        / 1024.00)
               ), 0.00) AS index_unused_memory_in_mb
FROM    sys.tables t
        JOIN sys.dm_db_xtp_table_memory_stats TMS ON ( t.object_id = TMS.object_id )

All Memory Used by Memory Optimized Table across Database Engine

-- this DMV accounts for all memory used by the hek_2 engine
SELECT type ,
name ,
memory_node_id ,
pages_kb / 1024 AS pages_MB
FROM sys.dm_os_memory_clerks
WHERE type LIKE '%xtp%'

Enable Natively Compiled Stored Procedure Stats Collection

EXEC [sys].[sp_xtp_control_proc_exec_stats] @new_collection_value = 1
DECLARE @c BIT
EXEC sp_xtp_control_proc_exec_stats @old_collection_value = @c OUTPUT
SELECT  @c AS 'collection status'

DBCC FREEPROCCACHE does not remove natively compiled stored procedures from Plan Cache

-- https://connect.microsoft.com/SQLServer/Feedback/Details/3126441

DECLARE @sql NVARCHAR(MAX) = N''

SELECT  @sql += N'EXECUTE sp_recompile N'''
        + QUOTENAME(SCHEMA_NAME(o.schema_id)) + N'.' + QUOTENAME(o.name) + '''
'
FROM    sys.sql_modules sm
        JOIN sys.objects o ON sm.object_id = o.object_id
WHERE   uses_native_compilation = 1

EXECUTE sp_executesql @sql


-- Reset wait and latch statistics.
DBCC SQLPERF('sys.dm_os_latch_stats' , CLEAR)
DBCC SQLPERF('sys.dm_os_wait_stats' , CLEAR)

Errors Encountered During Migration :

Msg 41317, Level 16, State 5, Line 6
A user transaction that accesses memory optimized tables or natively compiled modules cannot access more than one user database or databases model and msdb, and it cannot write to master.