Reduce first-run lookback from 3-7 days to 1 hour for all collectors (#335) (#340)

All 8 collectors with first-run backfill logic now look back 1 hour
instead of 3-7 days (or unlimited). The aggressive lookback was a
development convenience that becomes catastrophic on large environments
— particularly query_store_collector with XML plan decompression on
multi-GB Query Store databases, causing timeout→rollback→retry loops.

Changed collectors:
- 08_collect_query_stats: all DMV data → 1 hour
- 09_collect_query_store: 3 days → 1 hour
- 10_collect_procedure_stats: all DMV data → 1 hour
- 18_collect_cpu_utilization_stats: 7 days → 1 hour
- 22_collect_blocked_processes: 3 days → 1 hour
- 24_collect_deadlock_xml: 3 days → 1 hour
- 28_collect_system_health_wrapper: 3 days → 1 hour
- 29_collect_default_trace: all available → 1 hour

Clean install verified on sql2016 with zero errors.

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: erikdarlingdata

install/08_collect_query_stats.sql

@@ -107,16 +107,16 @@ BEGIN
         END;
 
         /*
-        First run detection - collect all queries if this is the first execution
+        First run detection - collect last 1 hour of queries if this is the first execution
         */
         IF NOT EXISTS (SELECT 1/0 FROM collect.query_stats)
         AND NOT EXISTS (SELECT 1/0 FROM config.collection_log WHERE collector_name = N'query_stats_collector')
         BEGIN
-            SET @cutoff_time = CONVERT(datetime2(7), '19000101');
+            SET @cutoff_time = DATEADD(HOUR, -1, SYSDATETIME());
 
             IF @debug = 1
             BEGIN
-                RAISERROR(N'First run detected - collecting all queries from sys.dm_exec_query_stats', 0, 1) WITH NOWAIT;
+                RAISERROR(N'First run detected - collecting last 1 hour of query stats', 0, 1) WITH NOWAIT;
             END;
         END;
         ELSE

install/09_collect_query_store.sql

@@ -145,16 +145,16 @@ BEGIN
         END;
 
         /*
-        First run detection - collect 3 days of history if this is the first execution
+        First run detection - collect last 1 hour of history if this is the first execution
         */
         IF NOT EXISTS (SELECT 1/0 FROM collect.query_store_data)
         AND NOT EXISTS (SELECT 1/0 FROM config.collection_log WHERE collector_name = N'query_store_collector')
         BEGIN
-            SET @cutoff_time = TODATETIMEOFFSET(DATEADD(DAY, -3, SYSUTCDATETIME()), 0);
+            SET @cutoff_time = TODATETIMEOFFSET(DATEADD(HOUR, -1, SYSUTCDATETIME()), 0);
 
             IF @debug = 1
             BEGIN
-                RAISERROR(N'First run detected - collecting last 3 days of Query Store data', 0, 1) WITH NOWAIT;
+                RAISERROR(N'First run detected - collecting last 1 hour of Query Store data', 0, 1) WITH NOWAIT;
             END;
         END;
         ELSE

install/10_collect_procedure_stats.sql

@@ -107,16 +107,16 @@ BEGIN
         END;
 
         /*
-        First run detection - collect all procedures if this is the first execution
+        First run detection - collect last 1 hour of procedures if this is the first execution
         */
         IF NOT EXISTS (SELECT 1/0 FROM collect.procedure_stats)
         AND NOT EXISTS (SELECT 1/0 FROM config.collection_log WHERE collector_name = N'procedure_stats_collector')
         BEGIN
-            SET @cutoff_time = CONVERT(datetime2(7), '19000101');
+            SET @cutoff_time = DATEADD(HOUR, -1, SYSDATETIME());
 
             IF @debug = 1
             BEGIN
-                RAISERROR(N'First run detected - collecting all procedures from sys.dm_exec_procedure_stats', 0, 1) WITH NOWAIT;
+                RAISERROR(N'First run detected - collecting last 1 hour of procedure stats', 0, 1) WITH NOWAIT;
             END;
         END;
         ELSE

install/18_collect_cpu_utilization_stats.sql

@@ -112,7 +112,7 @@ BEGIN
         /*
         Collect CPU utilization data from ring buffers
         Only collects samples newer than the most recent sample we have
-        On first run (NULL max_sample_time), looks back 7 days to populate initial data
+        On first run (NULL max_sample_time), looks back 1 hour to populate initial data
         Avoids duplicate collection of same ring buffer events
         */
         INSERT INTO
@@ -156,7 +156,7 @@ BEGIN
             SECOND,
             -((@current_ms_ticks - t.timestamp) / 1000),
             @start_time
-        ) > ISNULL(@max_sample_time, DATEADD(DAY, -7, @start_time))
+        ) > ISNULL(@max_sample_time, DATEADD(HOUR, -1, @start_time))
         ORDER BY
             t.timestamp DESC
         OPTION(RECOMPILE);

install/22_collect_blocked_processes.sql

@@ -140,17 +140,17 @@ BEGIN
         END;
 
         /*
-        First run detection - collect 3 days of history if this is the first execution
+        First run detection - collect last 1 hour of history if this is the first execution
         */
         IF NOT EXISTS (SELECT 1/0 FROM collect.blocked_process_xml)
         AND NOT EXISTS (SELECT 1/0 FROM config.collection_log WHERE collector_name = N'blocked_process_xml_collector')
         BEGIN
-            SET @minutes_back = 4320; /*3 days*/
+            SET @minutes_back = 60; /*1 hour*/
             SET @cutoff_time = DATEADD(MINUTE, -@minutes_back, SYSUTCDATETIME());
 
             IF @debug = 1
             BEGIN
-                RAISERROR(N'First run detected - collecting last 3 days of blocked process events', 0, 1) WITH NOWAIT;
+                RAISERROR(N'First run detected - collecting last 1 hour of blocked process events', 0, 1) WITH NOWAIT;
             END;
         END;
 

install/24_collect_deadlock_xml.sql

@@ -101,17 +101,17 @@ BEGIN
         END;
 
         /*
-        First run detection - collect 3 days of history if this is the first execution
+        First run detection - collect last 1 hour of history if this is the first execution
         */
         IF NOT EXISTS (SELECT 1/0 FROM collect.deadlock_xml)
         AND NOT EXISTS (SELECT 1/0 FROM config.collection_log WHERE collector_name = N'deadlock_xml_collector')
         BEGIN
-            SET @minutes_back = 4320; /*3 days*/
+            SET @minutes_back = 60; /*1 hour*/
             SET @cutoff_time = DATEADD(MINUTE, -@minutes_back, SYSUTCDATETIME());
 
             IF @debug = 1
             BEGIN
-                RAISERROR(N'First run detected - collecting last 3 days of deadlock events', 0, 1) WITH NOWAIT;
+                RAISERROR(N'First run detected - collecting last 1 hour of deadlock events', 0, 1) WITH NOWAIT;
             END;
         END;
 

install/28_collect_system_health_wrapper.sql

@@ -101,16 +101,16 @@ BEGIN
         END;
 
         /*
-        First run detection - collect 3 days of history if this is the first execution
+        First run detection - collect last 1 hour of history if this is the first execution
         */
         IF NOT EXISTS (SELECT 1/0 FROM config.collection_log WHERE collector_name = N'system_health_collector')
         BEGIN
-            SET @hours_back = 72; /*3 days*/
+            SET @hours_back = 1; /*1 hour*/
             SET @start_date = DATEADD(HOUR, -@hours_back, SYSDATETIMEOFFSET());
 
             IF @debug = 1
             BEGIN
-                RAISERROR(N'First run detected - collecting last 3 days of system health data', 0, 1) WITH NOWAIT;
+                RAISERROR(N'First run detected - collecting last 1 hour of system health data', 0, 1) WITH NOWAIT;
             END;
         END;
 

install/29_collect_default_trace.sql

@@ -110,17 +110,17 @@ BEGIN
         END;
 
         /*
-        First run detection - collect all available trace data if this is the first execution
+        First run detection - collect last 1 hour of trace data if this is the first execution
         Ignore CONFIG_CHANGE entries when checking for first run (those are just from enabling the trace)
         */
         IF NOT EXISTS (SELECT 1/0 FROM collect.default_trace_events)
         AND NOT EXISTS (SELECT 1/0 FROM config.collection_log WHERE collector_name = N'default_trace_collector' AND collection_status = N'SUCCESS')
         BEGIN
-            SET @cutoff_time = CONVERT(datetime2(7), '19000101');
+            SET @cutoff_time = DATEADD(HOUR, -1, SYSDATETIME());
 
             IF @debug = 1
             BEGIN
-                RAISERROR(N'First run detected - collecting all available default trace events', 0, 1) WITH NOWAIT;
+                RAISERROR(N'First run detected - collecting last 1 hour of default trace events', 0, 1) WITH NOWAIT;
             END;
         END;