Merge branch 'dev' of https://github.com/erikdarlingdata/DarlingData into dev

Author: erikdarlingdata

sp_PerfCheck/sp_PerfCheck.sql

@@ -310,7 +310,11 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
         @io_sql nvarchar(max) = N'',
         @file_io_sql nvarchar(max) = N'',
         @db_size_sql nvarchar(max) = N'',
-        @tempdb_files_sql nvarchar(max) = N'';
+        @tempdb_files_sql nvarchar(max) = N'',
+        /* TempDB pagelatch contention variables */
+        @pagelatch_wait_hours decimal(20,2),
+        @server_uptime_hours decimal(20,2),
+        @pagelatch_ratio_to_uptime decimal(10,4);
 
 
     /* Check for VIEW SERVER STATE permission */
@@ -926,7 +930,7 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
         url
     )
     SELECT
-        check_id = 4103,
+        check_id = 5103,
         priority =
             CASE
                 WHEN
@@ -1984,6 +1988,28 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
             ws.wait_time_percent_of_uptime DESC;
     END;
 
+    /* Calculate pagelatch wait time for TempDB contention check */
+    IF @has_view_server_state = 1
+    BEGIN
+        SELECT 
+            @pagelatch_wait_hours = 
+                SUM
+                (
+                    CASE 
+                        WHEN osw.wait_type IN (N'PAGELATCH_UP', N'PAGELATCH_SH', N'PAGELATCH_EX') 
+                        THEN osw.wait_time_ms / 1000.0 / 3600.0
+                        ELSE 0 
+                    END
+                ),
+            @server_uptime_hours = 
+                DATEDIFF(SECOND, osi.sqlserver_start_time, GETDATE()) / 3600.0
+        FROM sys.dm_os_wait_stats AS osw
+        CROSS JOIN sys.dm_os_sys_info AS osi;
+
+        SET @pagelatch_ratio_to_uptime = 
+            @pagelatch_wait_hours / NULLIF(@server_uptime_hours, 0) * 100;
+    END;
+
     /* Check for CPU scheduling pressure (signal wait ratio) */
     IF @has_view_server_state = 1
     BEGIN
@@ -3283,8 +3309,12 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
                 50, /* High priority */
                 N'TempDB Configuration',
                 N'Single TempDB Data File',
-                N'TempDB has only one data file. Multiple files can reduce allocation page contention. ' +
-                N'Recommendation: Use multiple files (equal to number of logical processors up to 8).',
+                N'TempDB has only one data file on a ' + CONVERT(nvarchar(10), @processors) + 
+                N'-core system. This creates allocation contention. Recommendation: Add ' +
+                CASE 
+                    WHEN @processors > 8 THEN N'8' 
+                    ELSE CONVERT(nvarchar(10), @processors)
+                END + N' data files total.',
                 N'https://erikdarling.com/sp_PerfCheck#tempdb'
             );
         END;
@@ -3426,6 +3456,43 @@ WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
             );
         END;
 
+        /* Check for TempDB allocation contention based on pagelatch waits */
+        IF  @tempdb_data_file_count <= @processors 
+        AND @tempdb_data_file_count < 8
+        AND @has_view_server_state = 1
+        AND @pagelatch_ratio_to_uptime >= 1.0
+        BEGIN
+            INSERT INTO
+                #results
+            (
+                check_id,
+                priority,
+                category,
+                finding,
+                details,
+                url
+            )
+            VALUES
+            (
+                2010,
+                40, /* High priority */
+                N'TempDB Performance',
+                N'TempDB Allocation Contention Detected',
+                N'Server has spent ' + 
+                CONVERT(nvarchar(20), CONVERT(decimal(10,2), @pagelatch_wait_hours)) + 
+                N' hours (' + 
+                CONVERT(nvarchar(10), CONVERT(decimal(5,2), @pagelatch_ratio_to_uptime)) + 
+                N'% of uptime) waiting on page latches. TempDB has ' + 
+                CONVERT(nvarchar(10), @tempdb_data_file_count) + 
+                N' data files. Consider adding files up to ' +
+                CASE 
+                    WHEN @processors > 8 THEN N'8'
+                    ELSE CONVERT(nvarchar(10), @processors)
+                END + N' total to reduce allocation contention.',
+                N'https://erikdarling.com/sp_PerfCheck#tempdb-contention'
+            );
+        END;
+
         /* Memory configuration checks */
         IF @min_server_memory >= (@max_server_memory * 0.9) /* Within 10% */
         BEGIN