diff --git a/alerting/src/main/kotlin/org/opensearch/alerting/DocumentLevelMonitorRunner.kt b/alerting/src/main/kotlin/org/opensearch/alerting/DocumentLevelMonitorRunner.kt
index 780971f7e..a1ffc44e4 100644
--- a/alerting/src/main/kotlin/org/opensearch/alerting/DocumentLevelMonitorRunner.kt
+++ b/alerting/src/main/kotlin/org/opensearch/alerting/DocumentLevelMonitorRunner.kt
@@ -25,8 +25,6 @@ import org.opensearch.alerting.model.MonitorRunResult
 import org.opensearch.alerting.model.userErrorMessage
 import org.opensearch.alerting.opensearchapi.suspendUntil
 import org.opensearch.alerting.script.DocumentLevelTriggerExecutionContext
-import org.opensearch.alerting.settings.AlertingSettings.Companion.PERCOLATE_QUERY_DOCS_SIZE_MEMORY_PERCENTAGE_LIMIT
-import org.opensearch.alerting.settings.AlertingSettings.Companion.PERCOLATE_QUERY_MAX_NUM_DOCS_IN_MEMORY
 import org.opensearch.alerting.util.AlertingException
 import org.opensearch.alerting.util.IndexUtils
 import org.opensearch.alerting.util.defaultToPerExecutionAction
@@ -237,25 +235,25 @@ class DocumentLevelMonitorRunner : MonitorRunner() {
                     }
 
                     val fieldsToBeQueried = mutableSetOf<String>()
-
-                    for (it in queries) {
-                        if (it.queryFieldNames.isEmpty()) {
-                            fieldsToBeQueried.clear()
+                        if (monitorCtx.fetchOnlyQueryFieldNames) {
+                        for (it in queries) {
+                            if (it.queryFieldNames.isEmpty()) {
+                                fieldsToBeQueried.clear()
+                                logger.debug(
+                                    "Monitor ${monitor.id} : " +
+                                        "Doc Level query ${it.id} : ${it.query} doesn't have queryFieldNames populated. " +
+                                        "Cannot optimize monitor to fetch only query-relevant fields. " +
+                                        "Querying entire doc source."
+                                )
+                                break
+                            }
+                            fieldsToBeQueried.addAll(it.queryFieldNames)
+                        }
+                        if (fieldsToBeQueried.isNotEmpty())
                             logger.debug(
-                                "Monitor ${monitor.id} : " +
-                                    "Doc Level query ${it.id} : ${it.query} doesn't have queryFieldNames populated. " +
-                                    "Cannot optimize monitor to fetch only query-relevant fields. " +
-                                    "Querying entire doc source."
+                                "Monitor ${monitor.id} Querying only fields " +
+                                    "${fieldsToBeQueried.joinToString()} instead of entire _source of documents"
                             )
-                            break
-                        }
-                        fieldsToBeQueried.addAll(it.queryFieldNames)
-                    }
-                    if (monitorCtx.fetchOnlyQueryFieldNames && fieldsToBeQueried.isNotEmpty()) {
-                        logger.debug(
-                            "Monitor ${monitor.id} Querying only fields " +
-                                "${fieldsToBeQueried.joinToString()} instead of entire _source of documents"
-                        )
                     }
 
                     // Prepare DocumentExecutionContext for each index
@@ -1028,7 +1026,7 @@ class DocumentLevelMonitorRunner : MonitorRunner() {
      *
      */
     private fun isInMemoryDocsSizeExceedingMemoryLimit(docsBytesSize: Long, monitorCtx: MonitorRunnerExecutionContext): Boolean {
-        var thresholdPercentage = PERCOLATE_QUERY_DOCS_SIZE_MEMORY_PERCENTAGE_LIMIT.get(monitorCtx.settings)
+        var thresholdPercentage = monitorCtx.percQueryDocsSizeMemoryPercentageLimit
         val heapMaxBytes = monitorCtx.jvmStats!!.mem.heapMax.bytes
         val thresholdBytes = (thresholdPercentage.toDouble() / 100.0) * heapMaxBytes
 
@@ -1036,7 +1034,7 @@ class DocumentLevelMonitorRunner : MonitorRunner() {
     }
 
     private fun isInMemoryNumDocsExceedingMaxDocsPerPercolateQueryLimit(numDocs: Int, monitorCtx: MonitorRunnerExecutionContext): Boolean {
-        var maxNumDocsThreshold = PERCOLATE_QUERY_MAX_NUM_DOCS_IN_MEMORY.get(monitorCtx.settings)
+        var maxNumDocsThreshold = monitorCtx.percQueryMaxNumDocsInMemory
         return numDocs >= maxNumDocsThreshold
     }
 
diff --git a/alerting/src/main/kotlin/org/opensearch/alerting/MonitorRunnerExecutionContext.kt b/alerting/src/main/kotlin/org/opensearch/alerting/MonitorRunnerExecutionContext.kt
index 01010a424..043ae88d4 100644
--- a/alerting/src/main/kotlin/org/opensearch/alerting/MonitorRunnerExecutionContext.kt
+++ b/alerting/src/main/kotlin/org/opensearch/alerting/MonitorRunnerExecutionContext.kt
@@ -52,4 +52,7 @@ data class MonitorRunnerExecutionContext(
     @Volatile var indexTimeout: TimeValue? = null,
     @Volatile var findingsIndexBatchSize: Int = AlertingSettings.DEFAULT_FINDINGS_INDEXING_BATCH_SIZE,
     @Volatile var fetchOnlyQueryFieldNames: Boolean = true,
+    @Volatile var percQueryMaxNumDocsInMemory: Int = AlertingSettings.DEFAULT_PERCOLATE_QUERY_NUM_DOCS_IN_MEMORY,
+    @Volatile var percQueryDocsSizeMemoryPercentageLimit: Int =
+        AlertingSettings.DEFAULT_PERCOLATE_QUERY_DOCS_SIZE_MEMORY_PERCENTAGE_LIMIT,
 )
diff --git a/alerting/src/main/kotlin/org/opensearch/alerting/MonitorRunnerService.kt b/alerting/src/main/kotlin/org/opensearch/alerting/MonitorRunnerService.kt
index 3af0e49a1..9cd3c2401 100644
--- a/alerting/src/main/kotlin/org/opensearch/alerting/MonitorRunnerService.kt
+++ b/alerting/src/main/kotlin/org/opensearch/alerting/MonitorRunnerService.kt
@@ -31,6 +31,8 @@ import org.opensearch.alerting.settings.AlertingSettings.Companion.INDEX_TIMEOUT
 import org.opensearch.alerting.settings.AlertingSettings.Companion.MAX_ACTIONABLE_ALERT_COUNT
 import org.opensearch.alerting.settings.AlertingSettings.Companion.MOVE_ALERTS_BACKOFF_COUNT
 import org.opensearch.alerting.settings.AlertingSettings.Companion.MOVE_ALERTS_BACKOFF_MILLIS
+import org.opensearch.alerting.settings.AlertingSettings.Companion.PERCOLATE_QUERY_DOCS_SIZE_MEMORY_PERCENTAGE_LIMIT
+import org.opensearch.alerting.settings.AlertingSettings.Companion.PERCOLATE_QUERY_MAX_NUM_DOCS_IN_MEMORY
 import org.opensearch.alerting.settings.DestinationSettings.Companion.ALLOW_LIST
 import org.opensearch.alerting.settings.DestinationSettings.Companion.HOST_DENY_LIST
 import org.opensearch.alerting.settings.DestinationSettings.Companion.loadDestinationSettings
@@ -188,6 +190,18 @@ object MonitorRunnerService : JobRunner, CoroutineScope, AbstractLifecycleCompon
             monitorCtx.fetchOnlyQueryFieldNames = it
         }
 
+        monitorCtx.percQueryMaxNumDocsInMemory = PERCOLATE_QUERY_MAX_NUM_DOCS_IN_MEMORY.get(monitorCtx.settings)
+        monitorCtx.clusterService!!.clusterSettings.addSettingsUpdateConsumer(PERCOLATE_QUERY_MAX_NUM_DOCS_IN_MEMORY) {
+            monitorCtx.percQueryMaxNumDocsInMemory = it
+        }
+
+        monitorCtx.percQueryDocsSizeMemoryPercentageLimit =
+            PERCOLATE_QUERY_DOCS_SIZE_MEMORY_PERCENTAGE_LIMIT.get(monitorCtx.settings)
+        monitorCtx.clusterService!!.clusterSettings
+            .addSettingsUpdateConsumer(PERCOLATE_QUERY_DOCS_SIZE_MEMORY_PERCENTAGE_LIMIT) {
+                monitorCtx.percQueryDocsSizeMemoryPercentageLimit = it
+            }
+
         return this
     }
 
diff --git a/alerting/src/main/kotlin/org/opensearch/alerting/settings/AlertingSettings.kt b/alerting/src/main/kotlin/org/opensearch/alerting/settings/AlertingSettings.kt
index de5b3bc81..19059dc1d 100644
--- a/alerting/src/main/kotlin/org/opensearch/alerting/settings/AlertingSettings.kt
+++ b/alerting/src/main/kotlin/org/opensearch/alerting/settings/AlertingSettings.kt
@@ -18,6 +18,8 @@ class AlertingSettings {
     companion object {
         const val DEFAULT_MAX_ACTIONABLE_ALERT_COUNT = 50L
         const val DEFAULT_FINDINGS_INDEXING_BATCH_SIZE = 1000
+        const val DEFAULT_PERCOLATE_QUERY_NUM_DOCS_IN_MEMORY = 50000
+        const val DEFAULT_PERCOLATE_QUERY_DOCS_SIZE_MEMORY_PERCENTAGE_LIMIT = 10
 
         val ALERTING_MAX_MONITORS = Setting.intSetting(
             "plugins.alerting.monitor.max_monitors",
@@ -44,7 +46,7 @@ class AlertingSettings {
          */
         val PERCOLATE_QUERY_MAX_NUM_DOCS_IN_MEMORY = Setting.intSetting(
             "plugins.alerting.monitor.percolate_query_max_num_docs_in_memory",
-            50000, 1000,
+            DEFAULT_PERCOLATE_QUERY_NUM_DOCS_IN_MEMORY, 1000,
             Setting.Property.NodeScope, Setting.Property.Dynamic
         )
 
diff --git a/alerting/src/test/kotlin/org/opensearch/alerting/DocumentMonitorRunnerIT.kt b/alerting/src/test/kotlin/org/opensearch/alerting/DocumentMonitorRunnerIT.kt
index 2928be59a..9406addf5 100644
--- a/alerting/src/test/kotlin/org/opensearch/alerting/DocumentMonitorRunnerIT.kt
+++ b/alerting/src/test/kotlin/org/opensearch/alerting/DocumentMonitorRunnerIT.kt
@@ -219,7 +219,7 @@ class DocumentMonitorRunnerIT : AlertingRestTestCase() {
         }
 
         val alerts = searchAlerts(monitor)
-        assertEquals("Alert saved for test monitor", 1, alerts.size)
+        assertEquals("Alert saved for test monitor", 0, alerts.size)
     }
 
     fun `test execute monitor returns search result with dryrun`() {