Add Off collection preset (#888)

CHANGELOG.md

@@ -15,6 +15,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - **Memory Pressure Events in Lite** — the collector, chart, and `get_memory_pressure_events` MCP tool previously only in the Full Edition are now available in Lite ([#865])
 - **Grid auto-scrolling** in Lite and Dashboard ([#843]) — thanks [@ClaudioESSilva](https://github.com/ClaudioESSilva)
+- **`Off` collection preset** — `config.apply_collection_preset @preset_name = N'Off'` disables every collector in one call. Pair it with a second Agent job that applies a non-`Off` preset at the start of your active window to get overnight / quiet-hours scoping without writing scheduler code. Non-`Off` presets now also set `enabled = 1` across the board so the switch reliably resumes collection ([#888])
 
 ### Changed
 
@@ -47,6 +48,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 [#865]: https://github.com/erikdarlingdata/PerformanceMonitor/issues/865
 [#867]: https://github.com/erikdarlingdata/PerformanceMonitor/issues/867
 [#872]: https://github.com/erikdarlingdata/PerformanceMonitor/issues/872
+[#888]: https://github.com/erikdarlingdata/PerformanceMonitor/issues/888
 
 ## [2.7.0] - 2026-04-13
 

README.md

@@ -56,7 +56,7 @@ All release binaries are digitally signed via [SignPath](https://signpath.io) 
 
 ## What You Get
 
-🔍 **32 specialized T-SQL collectors** running on configurable schedules with named presets (Aggressive, Balanced, Low-Impact) — wait stats, query performance, blocking chains, deadlock graphs, memory grants, file I/O, tempdb, perfmon counters, FinOps/capacity, and more. Query text and execution plan collection can be disabled per-collector for sensitive environments.
+🔍 **32 specialized T-SQL collectors** running on configurable schedules with named presets (Off, Aggressive, Balanced, Low-Impact) — wait stats, query performance, blocking chains, deadlock graphs, memory grants, file I/O, tempdb, perfmon counters, FinOps/capacity, and more. Query text and execution plan collection can be disabled per-collector for sensitive environments. Switch presets with a pair of SQL Agent jobs to get quiet-hours / overnight windows without writing any code.
 
 🚨 **Real-time alerts** for blocking, deadlocks, and high CPU — system tray notifications, styled HTML emails with full XML attachments, and webhook notifications for external integrations
 

install/41_schedule_management.sql

@@ -142,10 +142,18 @@ GO
 
 /*
 Apply a named collection preset
-Changes all scheduled collector frequencies in one operation.
-Does not modify enabled/disabled state or daily/on-load collectors.
 
-Valid preset names: Aggressive, Balanced, Low-Impact
+Valid preset names: Off, Aggressive, Balanced, Low-Impact
+
+Off sets enabled = 0 on every row in config.collection_schedule and changes
+nothing else — no frequency edits. The other three set enabled = 1 on every
+row (so switching back from Off reliably reactivates collection) and update
+frequency_minutes for the collectors they list. Daily/on-load collectors
+that aren't in the preset keep their existing frequency.
+
+Heads up: applying a non-Off preset overrides any manual
+UPDATE config.collection_schedule SET enabled = 0 on a specific collector.
+If that matters in your environment, re-disable it after switching presets.
 */
 IF OBJECT_ID(N'config.apply_collection_preset', N'P') IS NULL
 BEGIN
@@ -169,9 +177,33 @@ BEGIN
         @rows_updated bigint = 0;
 
     BEGIN TRY
-        IF @preset_name NOT IN (N'Aggressive', N'Balanced', N'Low-Impact')
+        IF @preset_name NOT IN (N'Off', N'Aggressive', N'Balanced', N'Low-Impact')
         BEGIN
-            RAISERROR(N'Invalid preset name "%s". Valid presets: Aggressive, Balanced, Low-Impact', 16, 1, @preset_name);
+            RAISERROR(N'Invalid preset name "%s". Valid presets: Off, Aggressive, Balanced, Low-Impact', 16, 1, @preset_name);
+            RETURN;
+        END;
+
+        /*
+        Off disables every collector and exits. No frequency table needed.
+        Pair with a second Agent job that applies a non-Off preset at the
+        start of your active window to resume collection.
+        */
+        IF @preset_name = N'Off'
+        BEGIN
+            UPDATE
+                config.collection_schedule
+            SET
+                enabled = 0,
+                modified_date = SYSDATETIME();
+
+            SET @rows_updated = ROWCOUNT_BIG();
+
+            IF @debug = 1
+            BEGIN
+                RAISERROR(N'Applied "Off" preset — %I64d collectors disabled', 0, 1, @rows_updated) WITH NOWAIT;
+            END;
+
+            PRINT 'Applied "Off" collection preset (' + CONVERT(varchar(10), @rows_updated) + ' collectors disabled)';
             RETURN;
         END;
 
@@ -303,20 +335,27 @@ BEGIN
         END;
 
         /*
-        Apply the preset to all matching collectors.
-        Only updates frequency - does not change enabled/disabled state.
-        Skips daily/on-load collectors not in the preset.
+        Re-enable every collector first so a switch from Off → named preset
+        reliably resumes collection, including daily/on-load collectors that
+        aren't in the preset frequency table.
+        */
+        UPDATE
+            config.collection_schedule
+        SET
+            enabled = 1,
+            modified_date = SYSDATETIME()
+        WHERE
+            enabled = 0;
+
+        /*
+        Apply the preset frequencies to the collectors it lists.
+        Daily/on-load collectors not in the preset keep their existing frequency.
         */
         UPDATE
             cs
         SET
             cs.frequency_minutes = p.frequency_minutes,
-            cs.next_run_time =
-                CASE
-                    WHEN cs.enabled = 1
-                    THEN SYSDATETIME()
-                    ELSE cs.next_run_time
-                END,
+            cs.next_run_time = SYSDATETIME(),
             cs.modified_date = SYSDATETIME()
         FROM config.collection_schedule AS cs
         JOIN @preset AS p
@@ -416,11 +455,12 @@ PRINT '';
 PRINT 'Available procedures:';
 PRINT '- config.update_collector_frequency - Change frequency for specific collector';
 PRINT '- config.set_collector_enabled - Enable/disable specific collector';
-PRINT '- config.apply_collection_preset - Apply a named preset (Aggressive, Balanced, Low-Impact)';
+PRINT '- config.apply_collection_preset - Apply a named preset (Off, Aggressive, Balanced, Low-Impact)';
 PRINT '- config.show_collection_schedule - Display current schedule';
 PRINT '';
 PRINT 'Examples:';
 PRINT '  EXECUTE config.apply_collection_preset @preset_name = N''Aggressive'', @debug = 1;';
 PRINT '  EXECUTE config.apply_collection_preset @preset_name = N''Balanced'';';
 PRINT '  EXECUTE config.apply_collection_preset @preset_name = N''Low-Impact'';';
+PRINT '  EXECUTE config.apply_collection_preset @preset_name = N''Off'';  -- disables all collectors';
 GO