MID Server runs into OOM issue during pattern output probe executionIssue <!-- /*NS Branding Styles*/ --> .ns-kb-css-body-editor-container { p { font-size: 12pt; font-family: Lato; color: var(--now-color--text-primary, #000000); } span { font-size: 12pt; font-family: Lato; color: var(--now-color--text-primary, #000000); } h2 { font-size: 24pt; font-family: Lato; color: var(--now-color--text-primary, black); } h3 { font-size: 18pt; font-family: Lato; color: var(--now-color--text-primary, black); } h4 { font-size: 14pt; font-family: Lato; color: var(--now-color--text-primary, black); } a { font-size: 12pt; font-family: Lato; color: var(--now-color--link-primary, #00718F); } a:hover { font-size: 12pt; color: var(--now-color--link-primary, #024F69); } a:target { font-size: 12pt; color: var(--now-color--link-primary, #032D42); } a:visited { font-size: 12pt; color: var(--now-color--link-primary, #00718f); } ul { font-size: 12pt; font-family: Lato; } li { font-size: 12pt; font-family: Lato; } img { display: ; max-width: ; width: ; height: ; } } MID Server runs into OOM issue during pattern output probe execution and can restart or go Down. Release<!-- /*NS Branding Styles*/ --> .ns-kb-css-body-editor-container { p { font-size: 12pt; font-family: Lato; color: var(--now-color--text-primary, #000000); } span { font-size: 12pt; font-family: Lato; color: var(--now-color--text-primary, #000000); } h2 { font-size: 24pt; font-family: Lato; color: var(--now-color--text-primary, black); } h3 { font-size: 18pt; font-family: Lato; color: var(--now-color--text-primary, black); } h4 { font-size: 14pt; font-family: Lato; color: var(--now-color--text-primary, black); } a { font-size: 12pt; font-family: Lato; color: var(--now-color--link-primary, #00718F); } a:hover { font-size: 12pt; color: var(--now-color--link-primary, #024F69); } a:target { font-size: 12pt; color: var(--now-color--link-primary, #032D42); } a:visited { font-size: 12pt; color: var(--now-color--link-primary, #00718f); } ul { font-size: 12pt; font-family: Lato; } li { font-size: 12pt; font-family: Lato; } img { display: ; max-width: ; width: ; height: ; } } Not release specific Cause<!-- /*NS Branding Styles*/ --> .ns-kb-css-body-editor-container { p { font-size: 12pt; font-family: Lato; color: var(--now-color--text-primary, #000000); } span { font-size: 12pt; font-family: Lato; color: var(--now-color--text-primary, #000000); } h2 { font-size: 24pt; font-family: Lato; color: var(--now-color--text-primary, black); } h3 { font-size: 18pt; font-family: Lato; color: var(--now-color--text-primary, black); } h4 { font-size: 14pt; font-family: Lato; color: var(--now-color--text-primary, black); } a { font-size: 12pt; font-family: Lato; color: var(--now-color--link-primary, #00718F); } a:hover { font-size: 12pt; color: var(--now-color--link-primary, #024F69); } a:target { font-size: 12pt; color: var(--now-color--link-primary, #032D42); } a:visited { font-size: 12pt; color: var(--now-color--link-primary, #00718f); } ul { font-size: 12pt; font-family: Lato; } li { font-size: 12pt; font-family: Lato; } img { display: ; max-width: ; width: ; height: ; } } MID by default is configured with 1GB JVM. During pattern output probe execution, the API call 'GetCITypes' from the MID Server to the instance within the pattern can consume almost all the available 1GB if there exists large number of custom tables which will cause OOM error and restarts the MID Server. Below error can be seen in MID logs for the pattern output probe execution:- 2025-12-30T22:55:39.699+0530 ERROR (Worker-Expedited:HorizontalDiscoveryProbe-1d15d90f47c23e102b2afa3c416d43d9) [PriorityThreadPoolProvider$PriorityThreadPoolExecutor:461] Thread: Worker-Expedited:HorizontalDiscoveryProbe-1d15d90f47c23e102b2afa3c416d43d9 terminated abnormallyjava.lang.OutOfMemoryError: Java heap spaceat java.base/java.util.HashMap.resize(HashMap.java:702)at java.base/java.util.HashMap.putVal(HashMap.java:661)at java.base/java.util.HashMap.put(HashMap.java:610)at com.snc.sw.kb.PatternLibraryEntity.addAttribute(PatternLibraryEntity.java:136)at com.snc.sw.kb.PatternLibraryLoader.parseCiTypesJson(PatternLibraryLoader.java:271)at com.snc.sw.kb.PatternLibraryLoader.fromJson(PatternLibraryLoader.java:147)at com.snc.sw.kb.PatternLibraryLoader.loadCITypes(PatternLibraryLoader.java:75)at com.snc.sw.kb.PatternLibraryLoader.load(PatternLibraryLoader.java:58)at com.snc.sw.kb.MidPatternLibrary.init(MidPatternLibrary.java:150)at com.snc.sw.kb.MidPatternLibrary.getPatternLibrary(MidPatternLibrary.java:41)at com.snc.sw.context.ExecutionContextFactory.initialize(ExecutionContextFactory.java:93)at com.snc.sw.context.ExecutionContextFactory.createImpl(ExecutionContextFactory.java:80)at com.snc.sw.context.ExecutionContextFactory.create(ExecutionContextFactory.java:67)at com.snc.sw.context.ExecutionContextFactory.create(ExecutionContextFactory.java:63)at com.snc.sw.context.ExecutionContextFactory.create(ExecutionContextFactory.java:59)at com.snc.sw.context.ExecutionContextFactory.createAppDiscovery(ExecutionContextFactory.java:210)at com.snc.sw.context.ExecutionContextFactory.createAppDiscovery(ExecutionContextFactory.java:222)at com.snc.sw.context.ExecutionContextFactory.createAppDiscovery(ExecutionContextFactory.java:228)at com.service_now.mid.probe.HorizontalDiscoveryProbe.runProbe(HorizontalDiscoveryProbe.java:170)at com.service_now.mid.probe.ServiceWatchProbe.probe(ServiceWatchProbe.java:40)at com.service_now.mid.probe.AProbe.process(AProbe.java:160)at com.service_now.mid.queue_worker.AWorker.runWorker(AWorker.java:187)at com.service_now.mid.queue_worker.AWorkerThread.run(AWorkerThread.java:20)at com.service_now.mid.threadpool.ResourceUserQueue$RunnableProxy.run(ResourceUserQueue.java:643)at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)at java.base/java.lang.Thread.run(Thread.java:840)----------------------------------------You can also observe the spike in "used" field of the 'LogStatusMonitor' in the MID Server logs even when single pattern output probe is being processed by the MID Server:-2025-12-30T22:39:55.850+0530 INFO (LogStatusMonitor.60) [LogStatusMonitor:54] 2025-12-30T17:09:55.838Z, stats threads: 107, memory max: 910.0mb, allocated: 262.0mb, used: 94.0mb, standard.queued: 0 probes, standard.processing: 1 probes, expedited.queued: 0 probes, expedited.processing: 0 probes, interactive.queued: 0 probes, interactive.processing: 0 probes2025-12-30T22:41:25.860+0530 INFO (LogStatusMonitor.60) [LogStatusMonitor:54] 2025-12-30T17:11:19.129Z, stats threads: 105, memory max: 910.0mb, allocated: 551.0mb, used: 91.0mb, standard.queued: 0 probes, standard.processing: 0 probes, expedited.queued: 0 probes, expedited.processing: 1 probes, interactive.queued: 0 probes, interactive.processing: 0 probes2025-12-30T22:42:16.332+0530 INFO (LogStatusMonitor.60) [LogStatusMonitor:54] 2025-12-30T17:12:16.322Z, stats threads: 106, memory max: 910.0mb, allocated: 116.0mb, used: 56.0mb, standard.queued: 0 probes, standard.processing: 1 probes, expedited.queued: 0 probes, expedited.processing: 0 probes, interactive.queued: 0 probes, interactive.processing: 0 probes2025-12-30T22:43:16.521+0530 INFO (LogStatusMonitor.60) [LogStatusMonitor:54] 2025-12-30T17:13:16.521Z, stats threads: 106, memory max: 910.0mb, allocated: 696.0mb, used: 538.0mb, standard.queued: 0 probes, standard.processing: 0 probes, expedited.queued: 0 probes, expedited.processing: 1 probes, interactive.queued: 0 probes, interactive.processing: 0 probes2025-12-30T22:44:39.356+0530 INFO (LogStatusMonitor.60) [LogStatusMonitor:54] 2025-12-30T17:14:30.405Z, stats threads: 105, memory max: 910.0mb, allocated: 854.0mb, used: 746.0mb, standard.queued: 0 probes, standard.processing: 0 probes, expedited.queued: 0 probes, expedited.processing: 1 probes, interactive.queued: 0 probes, interactive.processing: 0 probes2025-12-30T22:45:35.236+0530 INFO (LogStatusMonitor.60) [LogStatusMonitor:54] 2025-12-30T17:15:28.393Z, stats threads: 105, memory max: 910.0mb, allocated: 854.0mb, used: 746.0mb, standard.queued: 0 probes, standard.processing: 0 probes, expedited.queued: 0 probes, expedited.processing: 1 probes, interactive.queued: 0 probes, interactive.processing: 0 probes2025-12-30T22:46:17.845+0530 INFO (LogStatusMonitor.60) [LogStatusMonitor:54] 2025-12-30T17:16:17.845Z, stats threads: 106, memory max: 910.0mb, allocated: 860.0mb, used: 743.0mb, standard.queued: 0 probes, standard.processing: 0 probes, expedited.queued: 0 probes, expedited.processing: 1 probes, interactive.queued: 0 probes, interactive.processing: 0 probes2025-12-30T22:48:20.758+0530 INFO (LogStatusMonitor.60) [LogStatusMonitor:54] 2025-12-30T17:17:32.129Z, stats threads: 105, memory max: 910.0mb, allocated: 854.0mb, used: 746.0mb, standard.queued: 0 probes, standard.processing: 0 probes, expedited.queued: 0 probes, expedited.processing: 1 probes, interactive.queued: 0 probes, interactive.processing: 1 probes2025-12-30T22:55:39.782+0530 INFO (LogStatusMonitor.60) [LogStatusMonitor:54] 2025-12-30T17:25:39.781Z, stats threads: 105, memory max: 910.0mb, allocated: 490.0mb, used: 92.0mb, standard.queued: 0 probes, standard.processing: 0 probes, expedited.queued: 0 probes, expedited.processing: 1 probes, interactive.queued: 0 probes, interactive.processing: 0 probes2025-12-30T22:56:42.449+0530 INFO (LogStatusMonitor.60) [LogStatusMonitor:54] 2025-12-30T17:26:42.433Z, stats threads: 110, memory max: 910.0mb, allocated: 194.0mb, used: 99.0mb, standard.queued: 0 probes, standard.processing: 6 probes, expedited.queued: 0 probes, expedited.processing: 0 probes, interactive.queued: 0 probes, interactive.processing: 0 probes---------------------------------------- Resolution<!-- /*NS Branding Styles*/ --> .ns-kb-css-body-editor-container { p { font-size: 12pt; font-family: Lato; color: var(--now-color--text-primary, #000000); } span { font-size: 12pt; font-family: Lato; color: var(--now-color--text-primary, #000000); } h2 { font-size: 24pt; font-family: Lato; color: var(--now-color--text-primary, black); } h3 { font-size: 18pt; font-family: Lato; color: var(--now-color--text-primary, black); } h4 { font-size: 14pt; font-family: Lato; color: var(--now-color--text-primary, black); } a { font-size: 12pt; font-family: Lato; color: var(--now-color--link-primary, #00718F); } a:hover { font-size: 12pt; color: var(--now-color--link-primary, #024F69); } a:target { font-size: 12pt; color: var(--now-color--link-primary, #032D42); } a:visited { font-size: 12pt; color: var(--now-color--link-primary, #00718f); } ul { font-size: 12pt; font-family: Lato; } li { font-size: 12pt; font-family: Lato; } img { display: ; max-width: ; width: ; height: ; } } You need to increase the MID Server memory from the default 1GB (for e.g. 4GB or 8GB) using the below steps:-1. Login to the MID Server host machine.2. Stop the MID Server Service.3. Edit the wrapper-override.conf file located at <MID_Install_Path>\agent\conf\4. Uncomment the below line and set the value to 4096(4GB) or 8192(8GB) based on the host machine's available memory.#wrapper.java.maxmemory=10245. Save the file and restart the MID Server Service. Related Links<!-- /*NS Branding Styles*/ --> .ns-kb-css-body-editor-container { p { font-size: 12pt; font-family: Lato; color: var(--now-color--text-primary, #000000); } span { font-size: 12pt; font-family: Lato; color: var(--now-color--text-primary, #000000); } h2 { font-size: 24pt; font-family: Lato; color: var(--now-color--text-primary, black); } h3 { font-size: 18pt; font-family: Lato; color: var(--now-color--text-primary, black); } h4 { font-size: 14pt; font-family: Lato; color: var(--now-color--text-primary, black); } a { font-size: 12pt; font-family: Lato; color: var(--now-color--link-primary, #00718F); } a:hover { font-size: 12pt; color: var(--now-color--link-primary, #024F69); } a:target { font-size: 12pt; color: var(--now-color--link-primary, #032D42); } a:visited { font-size: 12pt; color: var(--now-color--link-primary, #00718f); } ul { font-size: 12pt; font-family: Lato; } li { font-size: 12pt; font-family: Lato; } img { display: ; max-width: ; width: ; height: ; } } Set the MID Server JVM memory size