# Copyright (C) 2019-present MongoDB, Inc. # # This program is free software: you can redistribute it and/or modify # it under the terms of the Server Side Public License, version 1, # as published by MongoDB, Inc. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # Server Side Public License for more details. # # You should have received a copy of the Server Side Public License # along with this program. If not, see # . # # As a special exception, the copyright holders give permission to link the # code of portions of this program with the OpenSSL library under certain # conditions as described in each individual source file and distribute # linked combinations including the program with the OpenSSL library. You # must comply with the Server Side Public License in all respects for # all of the code used other than as permitted herein. If you modify file(s) # with this exception, you may extend this exception to your version of the # file(s), but you are not obligated to do so. If you do not wish to do so, # delete this exception statement from your version. If you delete this # exception statement from all source files in the program, then also delete # it in the license file. # global: cpp_namespace: "mongo" cpp_includes: - "mongo/platform/atomic_proxy.h" - "mongo/platform/atomic_word.h" server_parameters: # # multi-plan ranking # internalQueryPlanEvaluationWorks: description: "Max number of times we call work() on plans before comparing them, for small collections." set_at: [ startup, runtime ] cpp_varname: "internalQueryPlanEvaluationWorks" cpp_vartype: AtomicWord default: 10000 validator: gt: 0 internalQueryPlanEvaluationCollFraction: description: "For large collections, the number times we work() candidate plans is taken as this fraction of the collection size." set_at: [ startup, runtime ] cpp_varname: "internalQueryPlanEvaluationCollFraction" cpp_vartype: AtomicDouble default: 0.3 validator: gte: 0.0 lte: 1.0 internalQueryPlanEvaluationMaxResults: description: "Stop working plans once a plan returns this many results." set_at: [ startup, runtime ] cpp_varname: "internalQueryPlanEvaluationMaxResults" cpp_vartype: AtomicWord default: 101 validator: gte: 0 internalQueryForceIntersectionPlans: description: "Do we give a big ranking bonus to intersection plans?" set_at: [ startup, runtime ] cpp_varname: "internalQueryForceIntersectionPlans" cpp_vartype: AtomicWord default: false internalQueryPlannerEnableIndexIntersection: description: "Do we have ixisect on at all?" set_at: [ startup, runtime ] cpp_varname: "internalQueryPlannerEnableIndexIntersection" cpp_vartype: AtomicWord default: true internalQueryPlannerEnableHashIntersection: description: "Do we use hash-based intersection for rooted $and queries?" set_at: [ startup, runtime ] cpp_varname: "internalQueryPlannerEnableHashIntersection" cpp_vartype: AtomicWord default: false # # Plan cache # internalQueryCacheMaxEntriesPerCollection: description: "The maximum number of entries allowed in a given collection's plan cache." set_at: [ startup, runtime ] cpp_varname: "internalQueryCacheMaxEntriesPerCollection" cpp_vartype: AtomicWord deprecated_name: "internalQueryCacheSize" default: 5000 validator: gte: 0 internalQueryCacheMaxSizeBytesBeforeStripDebugInfo: description: "Limits the amount of debug info stored across all plan caches in the system. Once the estimate of the number of bytes used across all plan caches exceeds this threshold, then debug info is not stored alongside new cache entries, in order to limit plan cache memory consumption. If plan cache entries are freed and the estimate once again dips below this threshold, then new cache entries will once again have debug info associated with them." set_at: [ startup, runtime ] cpp_varname: "internalQueryCacheMaxSizeBytesBeforeStripDebugInfo" cpp_vartype: AtomicWord default: expr: 512 * 1024 * 1024 validator: gte: 0 internalQueryCacheEvictionRatio: description: "How many times more works must we perform in order to justify plan cache eviction and replanning?" set_at: [ startup, runtime ] cpp_varname: "internalQueryCacheEvictionRatio" cpp_vartype: AtomicDouble default: 10.0 validator: gte: 0.0 internalQueryCacheWorksGrowthCoefficient: description: "How quickly the the 'works' value in an inactive cache entry will grow. It grows exponentially. The value of this server parameter is the base." set_at: [ startup, runtime ] cpp_varname: "internalQueryCacheWorksGrowthCoefficient" cpp_vartype: AtomicDouble default: 2.0 validator: gt: 1.0 internalQueryCacheDisableInactiveEntries: description: "Whether or not cache entries can be marked as 'inactive'." set_at: [ startup, runtime ] cpp_varname: "internalQueryCacheDisableInactiveEntries" cpp_vartype: AtomicWord default: false # # Parsing # internalPipelineLengthLimit: description: "The maximum length allowed for an an aggregation pipeline." set_at: [ startup ] cpp_varname: "internalPipelineLengthLimit" cpp_vartype: int default: 1000 validator: gt: 0 # # Planning and enumeration # internalQueryPlannerMaxIndexedSolutions: description: "How many indexed solutions will QueryPlanner::plan output?" set_at: [ startup, runtime ] cpp_varname: "internalQueryPlannerMaxIndexedSolutions" cpp_vartype: AtomicWord default: 64 validator: gte: 0 internalQueryEnumerationPreferLockstepOrEnumeration: description: "If set to true, instructs the plan enumerator to enumerate contained $ors in a special order. $or enumeration can generate an exponential number of plans, and is therefore limited at some arbitrary cutoff controlled by a parameter. When this limit is hit, the order of enumeration is important. For example, a query like the following has a 'contained $or' (within an $and): {a: 1, $or: [{b: 1, c: 1}, {b: 2, c: 2}]} For this query if there are indexes a_b={a: 1, b: 1} and a_c={a: 1, c: 1}, the normal enumeration order would output assignments [a_b, a_b], [a_c, a_b], [a_b, a_c], then [a_c, a_c]. This flag will instruct the enumerator to instead prefer a different order. It's hard to summarize, but perhaps the phrases 'lockstep enumeration', 'simultaneous advancement', or 'parallel iteration' will help the reader. The effect is to give earlier enumeration to plans which use the same choice across all branches. In this order, we would get assignments [a_b, a_b], [a_c, a_c], [a_c, a_b], then [a_b, a_c]. This is thought to be helpful in general, but particularly in cases where all children of the $or use the same fields and have the same indexes available, as in this example." set_at: [ startup, runtime ] cpp_varname: "internalQueryEnumerationPreferLockstepOrEnumeration" cpp_vartype: AtomicWord default: false internalQueryEnumerationMaxOrSolutions: description: "How many solutions will the enumerator consider at each OR?" set_at: [ startup, runtime ] cpp_varname: "internalQueryEnumerationMaxOrSolutions" cpp_vartype: AtomicWord default: 10 validator: gte: 0 internalQueryEnumerationMaxIntersectPerAnd: description: "How many intersections will the enumerator consider at each AND?" set_at: [ startup, runtime ] cpp_varname: "internalQueryEnumerationMaxIntersectPerAnd" cpp_vartype: AtomicWord default: 3 validator: gte: 0 internalQueryPlanOrChildrenIndependently: description: "Do we want to plan each child of the OR independently?" set_at: [ startup, runtime ] cpp_varname: "internalQueryPlanOrChildrenIndependently" cpp_vartype: AtomicWord default: true internalQueryMaxScansToExplode: description: "How many index scans are we willing to produce in order to obtain a sort order during explodeForSort?" set_at: [ startup, runtime ] cpp_varname: "internalQueryMaxScansToExplode" cpp_vartype: AtomicWord default: 200 validator: gte: 0 internalQueryPlannerGenerateCoveredWholeIndexScans: description: "Allow the planner to generate covered whole index scans, rather than falling back to a COLLSCAN." set_at: [ startup, runtime ] cpp_varname: "internalQueryPlannerGenerateCoveredWholeIndexScans" cpp_vartype: AtomicWord default: false internalQueryIgnoreUnknownJSONSchemaKeywords: description: "Ignore unknown JSON Schema keywords." set_at: [ startup, runtime ] cpp_varname: "internalQueryIgnoreUnknownJSONSchemaKeywords" cpp_vartype: AtomicWord default: false # # Query execution # internalQueryMaxBlockingSortMemoryUsageBytes: description: "The maximum amount of memory a query (e.g. a find or aggregate command) is willing to use to execute a blocking sort, measured in bytes. If disk use is allowed, then it may be possible to sort more data, but this limit will still constrain the memory consumption." set_at: [ startup, runtime ] cpp_varname: "internalQueryMaxBlockingSortMemoryUsageBytes" cpp_vartype: AtomicWord default: expr: 100 * 1024 * 1024 validator: gte: 0 internalQueryExecYieldIterations: description: "Yield after this many \"should yield?\" checks." set_at: [ startup, runtime ] cpp_varname: "internalQueryExecYieldIterations" cpp_vartype: AtomicWord default: 1000 internalQueryExecYieldPeriodMS: description: "Yield if it's been at least this many milliseconds since we last yielded." set_at: [ startup, runtime ] cpp_varname: "internalQueryExecYieldPeriodMS" cpp_vartype: AtomicWord default: 10 validator: gte: 0 internalQueryFacetBufferSizeBytes: description: "The number of bytes to buffer at once during a $facet stage." set_at: [ startup, runtime ] cpp_varname: "internalQueryFacetBufferSizeBytes" cpp_vartype: AtomicWord default: expr: 100 * 1024 * 1024 validator: gt: 0 internalQueryFacetMaxOutputDocSizeBytes: description: "The number of bytes to buffer at once during a $facet stage." set_at: [ startup, runtime ] cpp_varname: "internalQueryFacetMaxOutputDocSizeBytes" cpp_vartype: AtomicWord default: expr: 100 * 1024 * 1024 validator: gt: 0 internalLookupStageIntermediateDocumentMaxSizeBytes: description: "Maximum size of the result set that we cache from the foreign collection during a $lookup." set_at: [ startup, runtime ] cpp_varname: "internalLookupStageIntermediateDocumentMaxSizeBytes" cpp_vartype: AtomicWord default: expr: 100 * 1024 * 1024 validator: gte: { expr: BSONObjMaxInternalSize} internalDocumentSourceGroupMaxMemoryBytes: description: "Maximum size of the data that the $group aggregation stage will cache in-memory before spilling to disk." set_at: [ startup, runtime ] cpp_varname: "internalDocumentSourceGroupMaxMemoryBytes" cpp_vartype: AtomicWord default: expr: 100 * 1024 * 1024 validator: gt: 0 internalInsertMaxBatchSize: description: "Maximum number of documents that we will insert in a single batch." set_at: [ startup, runtime ] cpp_varname: "internalInsertMaxBatchSize" cpp_vartype: AtomicWord default: expr: internalQueryExecYieldIterations.load() / 2 is_constexpr: false validator: gt: 0 internalDocumentSourceCursorBatchSizeBytes: description: "Maximum amount of data that DocumentSourceCursor will cache from the underlying PlanExecutor before pipeline processing." set_at: [ startup, runtime ] cpp_varname: "internalDocumentSourceCursorBatchSizeBytes" cpp_vartype: AtomicWord default: expr: 4 * 1024 * 1024 validator: gte: 0 internalDocumentSourceLookupCacheSizeBytes: description: "Maximum amount of non-correlated foreign-collection data that the $lookup stage will cache before abandoning the cache and executing the full pipeline on each iteration." set_at: [ startup, runtime ] cpp_varname: "internalDocumentSourceLookupCacheSizeBytes" cpp_vartype: AtomicWord default: expr: 100 * 1024 * 1024 validator: gte: 0 internalQueryProhibitBlockingMergeOnMongoS: description: "If true, blocking stages such as $group or non-merging $sort will be prohibited from running on mongoS." set_at: [ startup, runtime ] cpp_varname: "internalQueryProhibitBlockingMergeOnMongoS" cpp_vartype: AtomicWord default: false internalQueryAllowShardedLookup: description: "If true, activates the incomplete sharded $lookup feature." set_at: [ startup, runtime ] cpp_varname: "internalQueryAllowShardedLookup" cpp_vartype: AtomicWord default: false internalQueryMaxJsEmitBytes: description: "Limits the vector of values emitted from a single document's call to JsEmit to the given size in bytes." set_at: [ startup, runtime ] cpp_varname: "internalQueryMaxJsEmitBytes" cpp_vartype: AtomicWord default: expr: 100 * 1024 * 1024 validator: gt: 0 internalQueryMaxPushBytes: description: "Limits the vector of values pushed into a single array while grouping with the $push accumulator." set_at: [ startup, runtime ] cpp_varname: "internalQueryMaxPushBytes" cpp_vartype: AtomicWord default: expr: 100 * 1024 * 1024 validator: gt: 0 internalQueryMaxAddToSetBytes: description: "Limits the vector of values pushed into a single array while grouping with the $addToSet accumulator." set_at: [ startup, runtime ] cpp_varname: "internalQueryMaxAddToSetBytes" cpp_vartype: AtomicWord default: expr: 100 * 1024 * 1024 validator: gt: 0 internalQueryJavaScriptHeapSizeLimitMB: description: "Limits the JavaScript heap size used in aggregation. Will defer to the global 'jsHeapLimitMB' limit if the global limit is smaller." set_at: [ startup, runtime ] cpp_varname: "internalQueryJavaScriptHeapSizeLimitMB" cpp_vartype: AtomicWord default: expr: 100 internalQueryJavaScriptFnTimeoutMillis: description: "Limits the maximum allowed time a user-defined javascript function can run in a query." set_at: [ startup, runtime ] cpp_varname: "internalQueryJavaScriptFnTimeoutMillis" cpp_vartype: AtomicWord default: expr: 60 * 1000 validator: gt: 0 internalQueryDesugarWhereToFunction: description: "When true, desugars $where to $expr/$function." set_at: [ startup, runtime ] cpp_varname: "internalQueryDesugarWhereToFunction" cpp_vartype: AtomicWord default: false internalQueryEnableSlotBasedExecutionEngine: description: "If true, activates the slot-based execution engine to execute queries." set_at: [ startup, runtime ] cpp_varname: "internalQueryEnableSlotBasedExecutionEngine" cpp_vartype: AtomicWord default: false internalQueryDefaultDOP: description: "Default degree of parallelism. This an internal experimental parameter and should not be changed on live systems." set_at: [ startup, runtime ] cpp_varname: "internalQueryDefaultDOP" cpp_vartype: AtomicWord default: 1 test_only: true validator: gt: 0 internalQueryEnableLoggingV2OplogEntries: description: "If true, this node may log $v:2 delta-style oplog entries." set_at: [ startup, runtime ] cpp_varname: "internalQueryEnableLoggingV2OplogEntries" cpp_vartype: AtomicWord default: true internalQuerySlotBasedExecutionMaxStaticIndexScanIntervals: description: "Limits the number of statically known intervals that SBE can decompose index bounds into when possible." set_at: [ startup, runtime ] cpp_varname: "internalQuerySlotBasedExecutionMaxStaticIndexScanIntervals" cpp_vartype: AtomicWord default: expr: 1000 validator: gt: 0 internalQueryEnableCSTParser: description: "If true, use the grammar-based parser and CST to parse queries." set_at: [ startup, runtime ] cpp_varname: "internalQueryEnableCSTParser" cpp_vartype: AtomicWord default: false internalQueryMaxDocValidationErrorConsideredValues: description: "Limits the number of values reported in the 'consideredValues' array when generating a descriptive document validation error." set_at: [ startup, runtime ] cpp_varname: "internalQueryMaxDocValidationErrorConsideredValues" cpp_vartype: AtomicWord default: expr: 10 validator: gt: 0