4.2 Changelog

4.2.20 Changelog

Sharding

SERVER-64903 Make cancel_coordinate_txn_commit_with_tickets_exhausted.js robust to ShardServerCatalogCacheLoader performing deletes

Aggregation

SERVER-41714 $facet operator duplicates documents in the pipeline when preceded by $addFields and $match operators (in this exact order)

Internals

SERVER-53726 Platform Support: Remove RHEL6 zSeries
SERVER-57000 Fix handling of correlated pipeline with facet
SERVER-57676 Wait for a checkpoint before releasing the "hangOplogCapMaintainerThread" in oplog_rollover.js
SERVER-59435 Fix a double free inside DocumentSource::optimizeAt()
SERVER-60412 Host memory limit check does not honor cgroups v2
SERVER-62242 $indexOfArray does not work with duplicate values in array
SERVER-63141 Difference in $lookup/$redact/$let behaviour with pipeline optimization
SERVER-64642 Fix error where mongos returns CallbackCanceled and not InterruptedAtShutdown on shutdown
SERVER-64983 Release Client lock before rolling back WT transaction in TransactionParticipant::_resetTransactionState
SERVER-65421 Fix package test failures on RHEL 6/7
SERVER-65422 Fix package test failures on Ubuntu 16.04

4.2.19 Changelog

Sharding

SERVER-26755 Collection chunk loading is aborted entirely if fetching all the chunks takes more than 30 seconds
SERVER-45149 replSetStepDown command in txn_two_phase_commit_failover.js should not timeout
SERVER-53335 Queries, updates, and deletes with non-"simple" collations may miss documents when using hashed sharding
SERVER-59929 unexpected slower update/insert operation bease of splitchunk and moveChunk
SERVER-60682 TransactionCoordinator may block acquiring WiredTiger write ticket to persist its decision, prolonging transactions being in the prepared state
SERVER-61816 cancel_coordinate_txn_commit_with_tickets_exhausted.js can hang forever due to race condition between transaction reaper and transaction coordinator
SERVER-61924 retryable_mongos_write_errors.js fails in 4.2 multiversion suites due to missing failpoint command in 4.0
SERVER-62065 Upgrade path from 3.6 to 4.0 can leave chunk entries without history on the shards
SERVER-62739 cancel_coordinate_txn_commit_with_tickets_exhausted.js test should not be run with the ephemeral storage engine
SERVER-62906 Add a check in the createCollection/shardCollection path verifying the collection name length

Query

SERVER-23664 $mod match expression should raise an error when the remainder is not a number
SERVER-40691 $nin:[[],...] queries are not indexed
SERVER-57588 Inconsistent query results when an array position is indexed whose value is an array
SERVER-59754 Incorrect logging of queryHash/planCacheKey for operations that share the same $lookup shape
SERVER-62147 Exhaust query using the OP_QUERY protocol is broken when more than one getMore batch is required

Aggregation

SERVER-44484 Changestream with updateLookup uasserts on updates from before collection was sharded

Storage

SERVER-55483 Add a new startup parameter that skips verifying the table log settings

Internals

SERVER-51087 Add testing utility for creating an empty sharded collection with the specified bounds
SERVER-53726 Platform Support: Remove RHEL6 zSeries
SERVER-57312 Pin transitive Python dependencies and use the pinned file for installation in Evergreen
SERVER-60392 Fix timing in priority_takeover_two_nodes_equal_priority test.
SERVER-60685 TransactionCoordinator may interrupt locally executing update with non-Interruption error category, leading to server crash
SERVER-61662 SCons configure checks should always run with verbosity
SERVER-61743 The -fno-builtin-memcmp flag shouldn't be applied except on x86_64 platforms
SERVER-62005 [4.2] Add requires_document_locking to unique_index_insert_during_collection_scan.js
SERVER-62164 Remove several obsoleted build variants across all stable branches
SERVER-62320 (v4.2) Fix use after std::move in find command
SERVER-62668 Synchronize access to ImpersonatedUserMetadata in OperationContext.
SERVER-62825 Robustify causally_consistent_index_builds.js
SERVER-63197 Pin microbenchmarks genny version
SERVER-63203 Chunk splitter never splits if more than 8192 split points are found
WT-7993 If gathering handles and not in aggressive eviction mode, have eviction sleep to let checkpoint grab a contentious spinlock.

4.2.18 Changelog

Sharding

SERVER-48504 Combination of StaleShardVersion and ShardNotFound exception make the ChunkManagerTargeter crash
SERVER-54064 Sessions on arbiters accumulate and cannot be cleared out
SERVER-54623 Decrease number of jobs in causal consistency passthrough suites
SERVER-56226 [v4.4] Introduce 'permitMigrations' field on config.collections entry to prevent chunk migrations from committing
SERVER-56227 Add user-facing command to set allowMigrations to false for a sharded collection
SERVER-58985 Re-enable retryable_mongos_write_errors.js in multiversion suite once SERVER-55648 is backported to v4.0
SERVER-59160 Disable balancer in test_stacked_migration_cleanup.js
SERVER-59916 T{1, 2}Starts{First, Second}AndWins In WriteConflictHelpers Does Not Synchronize Committing Of Failed Transaction
SERVER-60653 Backport the autoSplitVector logic to v4.2

Replication

SERVER-50241 PeriodicShardedIndexConsistencyChecker should skip dropped collections
SERVER-56096 Invariant failure in ReplicationRecoveryImpl::recoverFromOplog
SERVER-58988 Avoid sync source selection cycle during primary catchup.

Aggregation

SERVER-59613 $range expression should error if it exceeds memory limit

Storage

SERVER-45953 Exempt oplog readers from acquiring read tickets

Operations

SERVER-28953 Capture df (disk full) statistics in FTDC
SERVER-53242 Always log collmod command

Internals

SERVER-52976 [4.2] collection_validation.cpp isn't used anywhere in the 4.2 branch
SERVER-53726 Platform Support: Remove RHEL6 zSeries
SERVER-55589 replSetMaintenance command does not take the RSTL
SERVER-56326 Add a round() method to the Decimal128 class
SERVER-56602 Track usage of match expressions in serverStatus
SERVER-57557 [v4.4] Support running checkFCV() shell helper with mongos connection
SERVER-57605 Expose Decimal128 equality comparison helper to shell
SERVER-58104 config.system.sessions collection can end up with invalid chunks if it is dropped and re-sharded with a shard key other than _id
SERVER-58119 single_node_set_new_hostname.js needs to call replSetReconfig with an assert.soonNoExcept
SERVER-58183 _applyPrepareTransaction does not ensure prepareConflictBehavior is kIgnoreConflictAcceptWrites on retry attempts
SERVER-58192 Use more unique_ptrs in QueryPlannerAnalysis::analyzeSort()
SERVER-58780 [v4.4] Ensure that _shouldSetStableTimestamp gets restored to true if replSetInitiate fails
SERVER-59108 Resolve race with transaction operation not killed after step down
SERVER-59120 Create unit tests for commitChunksMerge
SERVER-59191 SPIKE: git.get_project fails to clone
SERVER-59226 Deadlock when stepping down with a profile session marked as uninterruptible
SERVER-59294 Check action type for oidReset
SERVER-59459 mongodb fails to build with glibc-2.34
SERVER-59725 Remove push task from extra RHEL 6.2 variants
SERVER-59804 Using a separate branch for YCSB in system_perf.yml
SERVER-59879 Adjust maxTimeMS value to allow for slower execution in the parallel test suite
SERVER-60080 [v4.2] Disable tests incompatible with ephemeralForTest
SERVER-60085 Cap number of fallback test suites at number of tests in suite
SERVER-60149 Add RRFaM build variant to mongocryptd list on v4.2 branch
SERVER-60290 Update Windows external auth test distro
SERVER-60299 Backport PCRE bugfix for Bugzilla #2613
SERVER-60456 LDAPBindOptions go out of scope during heavily delayed binds on Windows
SERVER-60496 Resmoke Misinterprets Quotes In Evergreen.yml
SERVER-60582 [v4.4] initiate_emrc_false.js needs to wait for the initial checkpoint
SERVER-60588 $multiply incorrectly throws an error in some cases in the classic engine
SERVER-60670 use a separate branch instead of a specific commit for TPCC
SERVER-60671 Remove dagger
SERVER-60897 [4.2] mongod may loop forever when attempting to upsert invalid BSON
SERVER-60898 [v4.2] Exclude stepdown_race_with_transaction.js from running on ephemeralForTest
SERVER-60961 Add exclude tags to old branches not generating multiversion_exclude_tags.yml
SERVER-60971 Remove calls to BF suggestion service
SERVER-61164 Accept error code 48 (Inappropriate authentication) as a valid response for LDAP liveness check
SERVER-61427 Unique index builds can cause a loss of availability during commit due to checking many false duplicates
SERVER-61544 [4.2] Fix exclusion tag for stepdown_race_with_transaction.js
SERVER-61550 Modify auto_workload_path in perf.yml to be relative to cwd
SERVER-61791 pin pymongo
WT-7566 Resolve write after free for dead dhandle
WT-7858 Fix malloc writing out of bounds for overflow keys
WT-7984 Fix a bug that could cause a checkpoint to omit a page of data

4.2.17 Changelog

Storage

SERVER-49521 fix tests in core/txn to use write concern "majority" for createIndexes commands run before starting transactions

Internals

SERVER-48090 Support python 3.6 for evergreen.py and shrub.py
SERVER-50549 Transform connection-related error codes in proxied commands
SERVER-53726 Platform Support: Remove RHEL6 zSeries
SERVER-59456 Start the LDAPReaper threadpool
SERVER-59876 Large delays in returning from libcrypto.so while establishing egress connections

4.2.16 Changelog

Security

SERVER-57727 Race conditions in x509_invalid.js

Sharding

SERVER-55648 Mongos doesn't return top-level batch-write error in case of shutdown
SERVER-58909 Missing versions for "admin" and "config" databases migrating to version 4.2

Replication

SERVER-34938 Secondary slowdown or hang due to content pinned in cache by single oplog batch
SERVER-36263 Bypassing operation validation in applyOps should require special privilege
SERVER-37904 Allow a node to override the cluster chaining (enabled/disabled) setting
SERVER-39621 Disabled chaining should enforce sync source change when the primary steps down even if the oplog fetcher isn't killed on sync source
SERVER-41875 Should ban "emptyCapped" commands on jstestfuzz_concurrent_replication_continuous__stepdown suite for WiredTiger Storage.
SERVER-50486 invokeWithSessionCheckedOut being called on prepared transactions on secondaries
SERVER-55465 Fix Invariant upon failed request for a vote from the current primary in the election dry-run of catchup takeover
SERVER-58258 Wait for initial sync to clear state before asserting 'replSetGetStatus' reply has no 'initialSync' field

Query

SERVER-55319 [4.2] Invariant failure isVersionInitialized() src/mongo/db/server_options.h 217 after index build completes
SERVER-58127 Fix benchRun() memory leak for parsing benchRun() args under exception

Build and Packaging

SERVER-54729 MongoDB Enterprise Debian/Ubuntu packages should depend on libsasl2-modules and libsasl2-modules-gssapi-mit

Internals

SERVER-49237 Add a way for OperationContexts to opt-in to always getting interrupted at stepdown
SERVER-50547 Explore aggregation pipeline length limit
SERVER-52728 Upgrade path from MongoDB 2.4 to 4.2 causes config servers to go down
SERVER-53431 Server should respond running operations with appropriate topologyVersion on stepdown
SERVER-53726 Platform Support: Remove RHEL6 zSeries
SERVER-55649 Sharding messages being logged for non-sharded clusters
SERVER-56489 New pass-through test with random hello server-side delays
SERVER-56516 Fix undefined behaviour in parsing code for $slice projectional operator
SERVER-56839 Index seeks concurrent with recently-committed prepared transactions can return wrong results
SERVER-57033 The AuthorizationManager Cache in 4.2 should use roles as cache key
SERVER-57064 Log create index and dropIndex(es) on mongos
SERVER-57360 Log additional debug info for the "invariant (_requests.empty());" in ~LockerImpl
SERVER-57642 Invariant Failure on src/mongo/db/query/plan_yield_policy.cpp 75 | Aborting
SERVER-57650 Make MigrationChunkClonerSource interruptible when waiting response to recipient commands
SERVER-57798 Direct user to MongoDB Compass download page when failing to install MongoDB Compass due to a connection issue using ./install_compass
SERVER-57983 Integer overflow for $range in Classic Engine
SERVER-58169 Log timestamps info on hitting invariants around stable timestamp calculation
SERVER-58187 Improve Connection Reaper and MongoLDAP performance
SERVER-58191 [Migrate Protocol] Allow delete_during_migrate.js to tolerate chunk migration failures due to timeout in catchup phase in slow variants.
SERVER-58283 Add a new versioning file to set MONGO_VERSION and MONGO_GIT_HASH
SERVER-58313 Fix package test failure caused by SERVER-55460 backport to v4.2 and v4.0
SERVER-58402 Increase timeout of shutdown command in shutdown_primary.js
SERVER-58623 Shorten the mongos RSM refresh interval in delayed Hello tests
SERVER-58826 [4.2] Disallow compact_keeps_indexes.js and explain_shell_helpers .js to run concurrently on parallel suite
SERVER-59074 Do not acquire storage tickets just to set/wait on oplog visibility
SERVER-59135 Make mongocryptd targets in MSIs depend on libsasl2
SERVER-59197 Delete fam image entries when the corresponding session documents are deleted
SERVER-59242 update to snmp 5.9.1
SERVER-59262 Remove burn_in_tests tasks from storeFindAndModifyImagesInSideCollection build variants
SERVER-59388 Revert BACKPORT-10185
SERVER-59414 Retry curator setup in powercycle on older branches
WT-6568 Fix split generation use
WT-6926 Update WiredTiger source code to include 2021 copyright notices
WT-7065 Add check for WT_DHANDLE_DEAD to assertion
WT-7135 Additional checks to detect when writing corrupted metadata
WT-7437 Upgrade documentation to doxygen 1.8.17
WT-7675 Query last ckpt timestamp changes without taking checkpoint
WT-7721 Update test-format to reopen an existing database with different config
WT-7776 Add a hard limit on the number of modify updates before we instantiate a complete update
WT-7871 Remove comment that is no longer true

4.2.15 Changelog

Security

SERVER-56240 Turn on checkpointing for the keystore Data Store

Sharding

SERVER-46811 multi=true updates can modify the shard key of orphan documents and cause them to become owned
SERVER-47534 Unblacklist mongos_dataSize.js from sharding_last_stable_mongos_and_mixed_shards suite
SERVER-47699 Change yield type used by range deleter from YIELD_MANUAL to YIELD_AUTO
SERVER-48648 Return updated ShardVersion in _configsvrCommitChunkMerge to avoid blind metadata refresh
SERVER-48653 Return updated ShardVersion in _configsvrCommitChunkSplit to avoid blind metadata refresh
SERVER-51170 Ensure database refreshes are performed after ShardingState initialization
SERVER-53029 Port the changes for SERVER-52955 to later branches
SERVER-56515 Chunk merge doesn't consider the incrementChunkMajorVersionOnChunkSplits parameter
SERVER-56654 Do not use the collection distributed lock for chunk splits
SERVER-56779 Do not use the collection distributed lock for chunk merges
SERVER-56786 There are three routing info refreshes and two chunk scans on the mergeChunks path
SERVER-57009 Additional debugging information in case of crash during FCV change
SERVER-57055 delete_during_migrate.js is consistently failing in test suites with Code Coverage enabled
SERVER-57102 Fixing invariants on ShardServerCatalogCacheLoader to consider different terms
SERVER-58109 The new '_configsvrMergeChunks' path is more expensive than the old one

Replication

SERVER-44316 Log message in InitialSyncer for setting begin applying timestamp is incorrect
SERVER-45919 replSetReconfig should be allowed to fail with InterruptedDueToReplStateChange when racing with an election
SERVER-53447 Blacklist insert1.js with from transaction passthrough tests with failures
SERVER-55465 Fix Invariant upon failed request for a vote from the current primary in the election dry-run of catchup takeover
SERVER-55766 Introduce an optimized "for restore" startup replication recovery mechanism
SERVER-56054 Change minThreads value for replication writer thread pool to 0
SERVER-56415 AwaitNodesAgreeOnPrimary doesn't work when given non-default set of nodes
SERVER-56937 upgradeSet() in multi_rs.js may lose authentication state while upgrading primary

Write Operations

SERVER-38909 Permit empty update modifiers, treating as a no-op rather than an error

Storage

SERVER-51699 index_build_restart_secondary.js (indexbg_restart_secondary.js) should handle exceptions when checking indexes after restarting node

Operations

SERVER-48567 Warnings while processing snmpwalk

Build and Packaging

SERVER-50568 Platform Support: Remove Ubuntu18.04 zSeries from 5.0
SERVER-55460 Fix RPM packaging and testing for SLES 12

Internals

SERVER-37125 Powercycle should ignore a process reference if it no longer exists
SERVER-43617 Add metrics on the mongos to indicate the number of shards targeted for the commands (find, aggregate, etc)
SERVER-45153 Ignore metrics temp files in FTDCFileManager
SERVER-47509 resmoke accepts multiple "mongodSetParameters" options but only uses the last one
SERVER-47720 Clarify "RecordId(...) not found in the index for key" log message
SERVER-48636 Increase assertEventDoesNotWakeCursor getMore timeout in only_wake_getmore_for_relevant_changes.js
SERVER-48890 allow $addFields with empty document and have it be a no-op
SERVER-49336 Set client metadata if it is missing during failCommand
SERVER-50955 oplog_rollover.js pauses the OplogCapMaintainerThread until truncation is needed
SERVER-53334 Hitting unexpected invariant failure, causing server shutdown
SERVER-53643 Startup can see old version of featureCompatibilityVersion document
SERVER-53726 Platform Support: Remove RHEL6 zSeries
SERVER-53728 Platform Support: Remove SLES12 zSeries
SERVER-53841 Additional logging for oplog_rollover.js
SERVER-54489 Full validation can append errors without bound
SERVER-54897 Adding the shard-single config to etc/system_perf.yml
SERVER-55019 install_compass does not run on all supported platforms
SERVER-55119 Create startup warning indicating that X.509 certificates without SANs are deprecated
SERVER-55316 Disconnect LDAP connections out of line
SERVER-55742 Define kmipClientCertificateSelector config on windows/macOS
SERVER-56062 Restart index builds after CappedPositionLost errors
SERVER-56164 All performance projects use the master DSI branch
SERVER-56273 Update curator hash in powercycle remote host setup
SERVER-56307 The chunk migration "convergence algorithm" is very primitive
SERVER-56310 Use w: majority for createCollection command in kill_sessions_with_prepared_transaction.js
SERVER-56325 Wait for failpoint in server_transaction_metrics.js to be hit so that a valid serverStatus is received
SERVER-56347 Enable LSE intrinsics in release
SERVER-56372 Add retryableFindAndModifyStorageLocation server parameter
SERVER-56373 [RRFaM] When writing FaM images to txn table, write oplog entries with needsRetryImage
SERVER-56374 [RRFaM] Have update path write to config.image_collection
SERVER-56375 [RRFaM] Have delete path write to config.transactions
SERVER-56376 [RRFaM] Add jstest that exercises both retryable FaM behaviors
SERVER-56377 [RRFaM] Add FSM test to perform retryable FaM while flipping server parameter
SERVER-56452 Self anchor in PooledLDAPConnection::setup's callback
SERVER-56468 Incorrect plan cache entry for {$ne: null} predicate, leads to missing query results
SERVER-56501 Add op counters for legacy op codes (OP_QUERY, OP_INSERT, etc.)
SERVER-56563 [RRFaM] Forge noop image oplog entries for chunk migration
SERVER-56630 Unittest OpObserverImpl::onDelete/onUpdate paths for retryable findAndModify
SERVER-56713 [RRFaM] Avoid creating images while in initial sync
SERVER-56715 Using incorrect var name for logkeeper dataset on 4.2
SERVER-56819 $indexOfCP returns incorrect result when searching for empty string inside empty string with non-zero start index (classic execution engine only)
SERVER-56952 [4.4] Add new build variant with storeFindAndModifyImagesInSideCollection=true
SERVER-57015 [RRFaM] Writing to the image collection must be in an UnreplicatedWriteBlock
SERVER-57036 Pin MarkupSafe == 1.1.0
SERVER-57043 Test for Branching
SERVER-57053 Rewriting $nor with a $text predicate to $not is invalid
SERVER-57057 Reduce routing info refreshes on the mergeChunks path
SERVER-57091 Infinite loop in GranularityRounderPreferredNumbers::roundDown
SERVER-57145 Invariant failure at OCSPManager::requestStatus
SERVER-57157 assert serverStatus command works in getBinVersion() jstest helper
SERVER-57172 Do json.send before DSI post_run
SERVER-57173 Write invalidated image for retryable findAndModify when secondaries apply operations earlier than minValid
SERVER-57233 Reap LDAP connections inline if multithreading is not enabled
SERVER-57273 remove the flow_control_replica_set.js test
SERVER-57275 Update kmip_server.py to be more verbose
SERVER-57299 Need to wait for failed exit code in startup_recovery_for_restore_needs_rollback.js
SERVER-57328 Make ReplsetTest.upgradeSet() tolerant of reelections
SERVER-57330 Update perf yaml configs for perf and sys-perf to use perf.send
SERVER-57476 Operation may block on prepare conflict while holding oplog slot, stalling replication indefinitely
SERVER-57490 [v4.2] Add storeFindAndModify build variant name to mongodcryptd list in etc/evergreen.yml
SERVER-57497 store_retryable_find_and_modify_images_in_side_collection.js should account for a later clustertime in retried findAndModify responses
SERVER-57544 Also backport store_retryable_find_and_modify_images_in_side_collection.js to 4.2
SERVER-57564 Increase system timeout duration to >2 hours to allow fio to copy over all files
SERVER-57708 ClientMetadata Parsing errors can leave ClientMetadataState decoration in invalid state
SERVER-57768 Deprecated counters aren't reset to zero on wrap
SERVER-57897 Add readPrefMode option to benchRun find/findOne ops
SERVER-57954 Update TPC-C version in sys-perf.yml

4.2.14 Changelog

Sharding

SERVER-52564 Deadlock between step down and MongoDOperationContextSession

Replication

SERVER-50412 Change “not master” error messages to “not primary”
SERVER-50414 Change “not master or secondary; cannot currently read from this replSet member” to “not primary or secondary; cannot currently read from this replSet member”
SERVER-54180 ReplSetTest's stepUp function only waits 6 seconds for nodes to agree on primary
SERVER-55007 Deadlock between step down and MongoDOperationContextSession

Query

SERVER-54710 Large number of $or clauses can create profiling entry exceeding max BSON size, causing the query to fail when it should not

Storage

SERVER-44821 retrieving storage stats for currentOp blocked by slow oplog application

Operations

SERVER-54770 Add /proc/meminfo MemAvailable to FTDC

Build and Packaging

SERVER-54031 errorcodes.py doesn't check embedded C++ code in Python scripts
SERVER-54057 Mongodb-org-server el8 package has dependency on python2
SERVER-54386 mongodb 3.6.22 install fails if systemctl daemon is not running
SERVER-55067 Migrate Windows builds to VS Current distro

Internals

SERVER-5722 Support a 'sort' field in ops array for JS Benchmarking Harness
SERVER-42944 scons compiledb exits with a stack trace
SERVER-49054 Server MSI should install Compass instead of Compass Community
SERVER-51465 Update package tests after compass installer update
SERVER-52610 Verify installation prefix is added to correct location in the RPM
SERVER-52833 Capped collections can contain too many documents after replication recovery
SERVER-52953 $geoNear does not always match coordinate given to 'near' when maxDistance is set to 0
SERVER-53566 Investigate and reproduce "opCtx != nullptr && _opCtx == nullptr" invariant
SERVER-54136 Make the authenticate command respect enforceUserClusterSeparation
SERVER-55038 Collect data files if zbigMapReduce.js fails
SERVER-55189 Call awaitReplication() before returning from syncFrom() in rslib.js
SERVER-55225 [v4.2] Collect data files for incremental_backup_rollback.js
SERVER-55395 4.0.23 does not build with gcc 10
SERVER-55602 Relax non-read-only invariant in WiredTigerKVEngine::makeTemporaryRecordStore when recoverToOplogTimestamp is specified
SERVER-55753 Use w: majority for createCollection command in transactions_committed_with_tickets_exhausted.js
SERVER-56164 All performance projects use the master DSI branch
SERVER-56371 Upgrade timelib to 2021.06
SERVER-56451 [4.2] update test for backup API to retry on conflict with checkpoint thread
WT-7373 Improve slow random cursor operations on oplog

4.2.13 Changelog

Sharding

SERVER-53236 Disable merge_with_move_primary.js from running on the sharding_csrs_continuous_config_stepdown suite
SERVER-53651 Just search for user-issued profiled aggregation in read_pref_cmd.js
SERVER-54014 Define a reasonable maxTimeMsOverride for the checkOID requests

Replication

SERVER-51163 Mark nodes returning InvalidReplicaSetConfig in heartbeats as down
SERVER-53248 call awaitLastOpCommitted before committing transaction in retryable_prepared_commit_transaction_after_failover.js
SERVER-53609 lastCommittedTransaction section causes frequent schema changes that limit FTDC retention
SERVER-53666 curSecondary in rollback test fixture not guaranteed to be in SECONDARY state after restart
SERVER-54339 Prevent spontaneous elections in rollback_crud_op_sequences.js
SERVER-54648 Add correct log verbosity to disallow_adding_initialized_node2.js

Query

SERVER-47869 Add diagnostic logging to ClusterCursorManager
SERVER-48442 Fix change_streams.js to test events in any order
SERVER-50073 Error message when creating a mixed hashed/not hashed index does not state the problem
SERVER-54660 Make jstests/sharding/kill_pinned_cursor.js more robust

Storage

SERVER-46876 During the eviction pressure, we should quit the compact operation instead of crashing the process
SERVER-54760 (4.2) Ghost timestamps can cause concurrent causal snapshot reads to not read their own writes

Build and Packaging

SERVER-52705 Rebuilding mongodb according to building.md failed because python3 is an alias/link (led to ModuleNotFoundError)
SERVER-54058 Update Debian 10 AMI for package testing
SERVER-54255 Update RHEL 7 AMI for package testing
SERVER-54858 Update Amazon Linux AMI for package testing

Internals

SERVER-35649 Nodes removed due to isSelf failure should re-attempt to find themselves
SERVER-43904 When stepping down, step up doesn't filter out frozen nodes
SERVER-44132 DataBuilder move assignment computes size incorrectly
SERVER-45836 Provide more LDAP details (like server IP) at default log level
SERVER-46686 Explain does not respect maxTimeMS
SERVER-46740 establishCursors() must always drain the AsyncRequestsSender::_baton
SERVER-47030 Fix date_time_support code to not produce exceptions
SERVER-49222 ARM64 support on Amazon Linux 2
SERVER-50592 Update mypy pip requirement
SERVER-51038 resmoke.py can't be run on python 3.8
SERVER-51722 Ensure that MongoDB builds with ARM LSE atomics
SERVER-52884 Remove race in reconstruct_prepared_transactions_initial_sync.js
SERVER-53196 Fail to generate tasks if a large distro is specified but not available
SERVER-53394 Make ShardingTaskExecutorPoolReplicaSetMatching default to disabled for MongoD
SERVER-53579 python's dev-requirements.txt is incompatible with pip 20.3.3
SERVER-53612 StepDown hangs until timeout if all nodes are caught up but none is immediately electable
SERVER-53717 Dynamically split large concurrency tasks
SERVER-53780 Fix missing quote in test parameters
SERVER-53831 Force SpiderMonkey to garbage collect in ReplSetTest.checkOplogs
SERVER-53836 Add multiversion-related expansions on Enterprise Ubuntu 16.04 (with {taskExecutorPoolSize=4}) build variant
SERVER-53932 Multikey write during recovery of prepared transaction could use commit timestamp < stable timestamp
SERVER-53992 Remove calls to detect-outliers from performance tasks
SERVER-54091 Update assertion messages for dbhash check run by resmoke.py
SERVER-54134 Ignore newer mongo versions on older branches of setup_multiversion_mongodb.py
SERVER-54139 Remove CURL share support from HTTP curl client
SERVER-54278 Add feature flag to disable Opportunistic Reads by default
SERVER-54366 Wait for node to start stepdown before killing shutdown operation in force_shutdown_primary.js
SERVER-54369 Update Jasper gRPC to latest version
SERVER-54458 updated vendored scons to use uuid for cache tmpfiles
SERVER-54484 resmoke/util/archival.py relies on deprecated and now removed thread.isAlive
SERVER-54505 Fix logic for ignored large distro build variants in 4.2
SERVER-54684 Decreased JS performance on arm64 due to mising init function
SERVER-54685 wrong definition of MONGO_YIELD_CORE_FOR_SMT for arm64
SERVER-54733 Enterprise Ubuntu 16.04 arm64 aggregation_multiversion_fuzzer failures
WT-6309 Add support for start/stop arguments to wt printlog command
WT-6430 Move WT_CONN_SERVER flags into their own field
WT-6844 Make force stop durable
WT-7026 Atomically read and set ref->addr in case of race
WT-7027 Run the metadata checkpoint for force_stop at read-committed isolation for incremental backup
WT-7028 Sweep thread shouldn't lock during checkpoint gathering handles
WT-7104 Redact user data from printlog output

4.2.12 Changelog

Sharding

SERVER-46393 Always check client last operation time when computing operationTime to append to the response
SERVER-50900 Disable PeriodicShardedIndexConsistencyChecker for cursor_valid_after_shard_stepdown.js
SERVER-52732 Uptime reporter disables autosplit during ShardingTest initialization
SERVER-53444 Make tests that run removeShard in assert.soon to wait for the state to become "completed" not error on ShardNotFound

Replication

SERVER-49187 Make ReplSetTest .stepUp() robust to election failures.
SERVER-50049 assert.soonNoExcept() should not access TestData.traceExceptions for non-resmoke tests.
SERVER-50416 Change notMasterLegacyUnacknowledgedWrites to notPrimaryLegacyUnacknowledgedWrites in serverStatus
SERVER-50417 Change notMasterUnacknowledgedWrites to notPrimaryUnacknowledgedWrites in serverStatus
SERVER-50869 Background sync may erroneously set applied-through during step-up
SERVER-50901 RollbackTest should wait for secondaries before doing data consistency checks
SERVER-52560 oplog_writes_only_permitted_on_standalone.js must wait for insert to be in stable checkpoint
SERVER-52680 Removed node on startup stuck in STARTUP2 after being re-added into the replica set
SERVER-52744 rollback node's lastApplied > sync source's lastApplied in rollback_after_enabling_majority_reads.js
SERVER-53026 Secondary cannot restart replication
SERVER-53345 Excuse arbiter_new_hostname.js from multiversion tests

Query

SERVER-32960 $mod has inconsistent rounding/truncation behavior
SERVER-40361 Reduce memory footprint of plan cache entries
SERVER-50769 server restarted after expr：{"expr":"_currentApplyOps.getArrayLength() > 0","file":"src/mongo/db/pipeline/document_source_change_stream_transform.cpp","line":535}}

Aggregation

SERVER-34741 Move $match in front of $group if condition is on group key
SERVER-40090 DISTINCT_SCAN in agg is only used when certain format of _id is specified
SERVER-51886 $lookup + $merge pipeline may fail to resolve views correctly when collection names collide

Storage

SERVER-47812 Secondaries persist wildcard multikeypaths out of order
SERVER-48471 Hashed indexes may be incorrectly marked multikey and be ineligible as a shard key
SERVER-51858 Investigate queryable issue on 4.0.20
SERVER-52950 recoverOplogAsStandalone mode must not start oplog truncater thread
SERVER-53703 [4.2] Opening a transaction at the all durable timestamp can go backwards

Build and Packaging

SERVER-52891 Run PPC builds less frequently

Internals

SERVER-41836 Log thread Id as part of error in FSM tests
SERVER-43739 SNI name is not set on OSX if allowInvalidHostnames is enabled
SERVER-44375 fix merge_with_drop_shard.js when the curop command fails due to ShardNotFound
SERVER-47863 Initial Sync Progress Metrics
SERVER-48742 Log whenever profiler settings are changed via setProfilingLevel
SERVER-50267 Set output limit for 'rawMongoProgramOutput()'
SERVER-50445 Return the value as double when NumberLong subtraction overflows in ExpressionSubtract
SERVER-51526 Hybrid index builds can miss writes and crash in the event of a well-timed WriteConflictException
SERVER-51607 Upgrade Twisted dependency to at least twisted-19.7.0
SERVER-52618 Sparse hash index should not be used for equality to null match
SERVER-52646 Validate and possibly fix edge cases in regex rewrite rules for userToDNMapping
SERVER-52654 new signing keys not generated by the monitoring-keys-for-HMAC thread
SERVER-52806 deb install files assume systemd
SERVER-52879 Periodic operation latency spikes every 5 minutes due to closing idle cached WT sessions
SERVER-52919 Wire compression not enabled for initial sync
SERVER-52929 Correctly handle compound indexes with 32 keys
SERVER-52969 Disable Powercyle on non-master branches
SERVER-52975 Fix use of 'onRollback' callback for collection validator options in 'collection_impl.cpp'
SERVER-53233 Fix change_streams_update_lookup_shard_metadata_missing.js [4.2, 4.0]
SERVER-53234 jstests/core/profile2.js fails when background operations are run against test database
WT-6835 Add API to allow consolidating incremental backup info
WT-6839 Add API to query existing incremental backup IDs
WT-6882 Files created during incremental backup should be copied in full
WT-6922 Add random consolidate testing to incr_backup

4.2.11 Changelog

Security

SERVER-45938 Allow matching O/OU/DC in client x509 cert if clusterMode:keyFile

Sharding

SERVER-36739 Use the mongos_manual_intervention_action hook in concurrency stepdown suites
SERVER-47616 Improve error when logical sessions cannot have more than one user authenticated on a single connection
SERVER-51808 invariant failure: readConcern level != Available

Replication

SERVER-33747 Arbiter tries to start data replication if cannot find itself in config after restart
SERVER-50116 Forbid oplog writes when replication is enabled
SERVER-50415 Rename waitInIsMaster failpoint to waitInHello
SERVER-50527 Change NotMasterError category to NotPrimaryError

Query

SERVER-51120 Find queries with SORT_MERGE incorrectly sort the results when the collation is specified
SERVER-51853 Always initialize the numInserted out-parameter in AbstractIndexAccessMethod::insertKeys

Write Operations

SERVER-44586 add metrics to serverStatus to track type of update command

Aggregation

SERVER-48523 Unconditionally check the first entry in the oplog when attempting to resume a change stream

Storage

SERVER-43664 Speedup WiredTiger storage engine startup for many tables by optimizing WiredTigerUtil::setTableLogging()

Operations

SERVER-46729 Make Windows shell soft-fail for unavailable OCSP responder
SERVER-51757 Collect /proc/vmstat numa_pages_migrated statistics in FTDC

Build and Packaging

SERVER-46342 DEB installs of MDB do not issue systemctl daemon-reload on install
SERVER-50016 Fail on missing variable customization files

Internals

SERVER-43973 jsTestName() should return a unique name for each thread in the parallel suite
SERVER-45992 InMemory engine startupwarnings confusing
SERVER-46625 Improve diagnostics when mongocryptd requests are sent to non-mongocryptd daemon
SERVER-48078 Remove OpDebug invariant that relies on monotonic clock source
SERVER-48502 Tighten $currentOp and pinned cursor checks in kill_pinned_cursor.js
SERVER-49165 endSessions command in Client.Disconnect causes an authorization failure for an unauthed connection on a host that requires authentication
SERVER-49957 Read out of bounds in getPrevAndNextUUIDs
SERVER-50072 Check _isWindows() when initializing MongoRunner.EXIT_ABORT
SERVER-50123 Record number of physical cores on all platforms
SERVER-50216 Adjust sys-perf frequencies
SERVER-50365 Stuck with long-running transactions that can't be timed out
SERVER-50605 Add {logMessage: "msg"} test-only command
SERVER-50647 Fix OCSP HTTP Client timeout for Windows
SERVER-50736 Make OpenSSL explicitly accept SNIs presented in ClientHello
SERVER-50818 Coverity analysis defect 114987: Wrapper object use after free
SERVER-51004 Disable WT-Develop sys-perf build variants on sys-perf-4.2
SERVER-51058 log_remote_op_wait.js misuses rawMongoProgramOutput
SERVER-51106 Make the isMaster command a derived class of hello
SERVER-51220 Handle auditing attribution in indirect drops
SERVER-51303 Lookup stage followed by $match on type uses wrong field in matching condition
SERVER-51840 Reduce dbtest jobs on 4.2 on Windows debug
TOOLS-2588 [v4.2] sslAllowInvalidHostnames bypass ssl/tls server certification validation entirely
WT-6160 Fix format failure caused by stack overwrite
WT-6507 Exit cache eviction worker after our operation has timed out
WT-6602 Allow operation timeout ms to be passed to commit and rollback
WT-6666 Start op timer when we configure it in rollback and commit

4.2.10 Changelog

Security

SERVER-50463 Make PooledLDAPConnection::refresh take self-ownership

Sharding

SERVER-37422 Log balancer start and stop events in the actionlog
SERVER-48601 ChunkSplitter should use the same chunk bounds for splitVector and splitChunk
SERVER-48679 flushRoutingTableCacheUpdates should block on critical section with kWrite, not kRead
SERVER-50889 migration_failure.js should run setFCV through the router instead of the config server

Replication

SERVER-47263 Inaccurate log message when losing dry run election
SERVER-47645 Must invalidate all sessions on step down
SERVER-48518 Rollback via refetch (EMRC = false) can make readers to see the rolled back data even after the rollback node catches up to primary.
SERVER-48928 Allow primary-elect to complete drain mode even if it is stepping down unconditionally
SERVER-49986 Convert isMaster command to hello and add aliases
SERVER-49987 Rename response fields if “hello” is sent on mongod
SERVER-49988 Rename response fields if "hello" is sent on mongos
SERVER-49989 Add db.hello() shell helper
SERVER-49990 Alias setSlaveOk() and getSlaveOk() shell helpers
SERVER-49991 Alias printSlaveReplicationInfo() shell helper
SERVER-50405 Alias isMaster in mongocryptd and attach appropriate response field
SERVER-50607 Must hold mutex when calling _checkForShutdownAndConvertStatus_inlock
SERVER-50626 Race in read_concern_majority_getmore_secondaries.js
SERVER-50640 listCommands should return "isMaster" alias in addition to "hello" command name

Query

SERVER-47469 applyOps does not take exclusive lock for views operation
SERVER-50291 Add query knob to enumerate $or children in a different order

Aggregation

SERVER-31368 Log time spent waiting for other shards in merge cursors aggregation stage
SERVER-40317 $facet execution has no limit on how much memory it can consume

Operations

SERVER-26726 Check number of arguments for createIndex() and throw error if more than two arguments

Build and Packaging

SERVER-23668 scons abbreviated options do not work properly
SERVER-44632 Platform Support: Remove Community zSeries from 4.2
SERVER-47138 MSI installer produces incorrect config file
SERVER-50078 Compile bypass applied when it should not have

Internals

SERVER-42852 buildStages() STAGE_SHARDING_FILTER block should hold child stage tree by unique_ptr
SERVER-43233 Add ability to request only specific attribute(s) for the LDAP groups
SERVER-45202 Improve Command alias infrastructure
SERVER-47428 Move concurrency_sharded* Evergreen tasks to -large distros
SERVER-48048 Use resmoke tag files for multiversion blacklisting
SERVER-48410 Signed integer overflow fix for datetime library
SERVER-48709 signing key generator thread on config server not waken up as expected
SERVER-49054 Server MSI should install Compass instead of Compass Community
SERVER-49438 Allow memory.js tests to accept $where timeout interruption
SERVER-49766 Indexed and non-indexed collections return different results for null query
SERVER-49786 Freeze DSI and Genny for non-master perf projects
SERVER-49922 Make schema_validator_with_expr_variables.js less heavy
SERVER-50183 Copy _awaitPrimaryAppliedSurpassesRollbackApplied function from RollbackTest to RollbackTestDeluxe
SERVER-50326 Restrict sharding in agg_out.js workload to a single thread
SERVER-50394 mongod audit log attributes DDL operations to the __system user in a sharded environment
SERVER-50403 Build server on combined visual studio image
SERVER-50760 [v4.2] Switch MultiOplogEntrySyncTailTest to use wiredTiger
SERVER-50822 [4.2] dont_read_oplog_hole_on_step_up.js should wait for all nodes to agree on a primary
SERVER-51041 Throttle starting transactions for secondary reads
WT-6000 Enhance incremental backup testing in format to support restart
WT-6215 Clear backup block information on rename: Reverted
WT-6421 Avoid parsing metadata checkpoint for clean files
WT-6539 Fix backup and rename memory leak
WT-6559 Use the session id from the new session to determine statistics bucket
WT-6598 Add new API allowing changing dhandle hash bucket size
WT-6610 Fix incremental backup checkpoint parsing to handle upgrades
WT-6611 Revert enhancement allowing rename and incremental backup

4.2.9 Changelog

Security

SERVER-47733 SymmetricEncryptorWindows shouldn't pad when update is called

Sharding

SERVER-40441 Arbiter nodes log error messages when try to create session collection or check if it exists
SERVER-46194 Applying transfer mods in a migration does not handle write conflicts
SERVER-48096 PeriodicShardedIndexConsistencyChecker thread on jstests can cause unintended shard refreshes
SERVER-48229 Shutdown PeriodicShardedIndexConsistencyChecker after ReplicationCoordinator so no thread will try to pause the job after it has stopped
SERVER-48491 Add requires_document_locking tag to sessions_collection_reaping.js
SERVER-48674 Check if replication is enabled before checking if the node is an arbiter in LogicalSessionCacheImpl
SERVER-48926 Fix remaining sharding tests that incorrectly set votes to 0 on shard secondaries
SERVER-49233 Introduce a flag to toggle the logic for bumping collection's major version during split
SERVER-49311 PeriodicShardedIndexConsistencyChecker might cause failures on stale_mongos_and_restarted_shards_agree_on_shard_version.js

Replication

SERVER-44779 Invariant internal operations that hit a prepareConflict must be marked killable
SERVER-45610 Some reads work while system is RECOVERING
SERVER-47849 Add more logging to shutdownTask
SERVER-48525 Forbid dropping config.transactions when there are prepared transactions
SERVER-48527 Aborting in-progress transactions on step-up should clear session state before returning
SERVER-48576 Fix the election race in change_stream_stepdown.js
SERVER-48611 speculative_majority_find.js should call awaitLastOpCommitted before running majority read that is expected to succeed
SERVER-48712 Race in write_concern_after_stepdown.js
SERVER-48778 Make reconstruct_prepared_transactions_initial_sync.js robust to election failures.
SERVER-48967 Prevent replicated writes on empty namespaces on secondaries
SERVER-48979 Race between config propagation and election in change_stream_stepdown.js
SERVER-49471 Retry on WT_ROLLBACK when applying prepareTransaction oplog entry
SERVER-50039 Timing error in dbadmin.js test

Query

SERVER-35921 Index scan uses incorrect bounds for MinKey and MaxKey
SERVER-44273 Failure to parse certain time zone specifications on windows platforms.
SERVER-45233 Indexed inequalities to arrays return incorrect results
SERVER-47223 geoNear/$geoNear does not apply index hints
SERVER-48614 Plan cache key computation for wildcard indexes with partialIndexFilter is incorrect, leading to incorrect query results
SERVER-48950 Enhance explain for $search to expose stats from mongot
SERVER-48993 explodeForSort can produce incorrect query plan
SERVER-49527 recoverFromOplogAsStandalone does not relax index constraints

Catalog

SERVER-47714 Secondary asserts on system.profile collection with WiredTigerRecordStore::insertRecord 95: Operation not supported

Storage

SERVER-44529 Re-acquiring locks after a yield and step down results in wrong parameters on recoveryUnit
SERVER-48274 Remove readOnly mode for queryable restores of encrypted sharded clusters
SERVER-48453 Lazily initialize a record store's auto incrementing counter on deletes
SERVER-48695 setAppliedThrough must set orderedCommit=false on the recovery unit

Operations

SERVER-44051 getShardDistribution() does not report "Collection XYZ is not sharded" on dropped but previously sharded collections
SERVER-48244 Shell should not hard-code the allowed explain levels and let the server reject it instead

Build and Packaging

SERVER-42042 Warn or fail early on dynamic builds with toolchain compiler and tcmalloc
SERVER-46445 MongoDB MSI installer showing irrelevant error message while installing in server configuration window
SERVER-48329 Adjust naming of action_type.h on either master or all stable branches
SERVER-48640 Update RHEL 6.2 AMI for package tests

Internals

SERVER-33229 Overload startParallelShell in auto_retry_on_network_error.js to connect after loading the auto_retry_on_network_error.js override
SERVER-41070 Add blockConnection mode to failCommand
SERVER-43490 Validate if we can perform TODO listed in SERVER-38686
SERVER-46721 Step up may cause reads at PIT with holes after yielding
SERVER-46854 Disable periodic index consistency checker on config servers in jstests/sharding/lookup_mongod_unaware.js
SERVER-47195 Allow failCommand failpoint to trigger only on a specific MongoClient
SERVER-47883 Newly-elected primaries do not wait for single-phase background index builds to complete before accepting writes
SERVER-47930 Ubuntu 20.04 - ldap_authz_authn.js fails to load test certificate
SERVER-48032 Update references of community mailing-lists to MongoDB Developer Community Forums
SERVER-48058 Make sure abort_transactions_on_step_up waits for optime to be applied
SERVER-48067 Reduce memory consumption for unique index builds with large numbers of non-unique keys
SERVER-48107 Retry replSetStepDown in rollback_test.js
SERVER-48514 Separate testing 'called' and 'successful' fields for serverStatus election metrics
SERVER-48532 [4.2] IndexBuildInterceptor::areAllWritesApplied may return false despite all records being visibly applied
SERVER-48568 Use 'nodeOptions' in change_streams_multi_version_transaction.js
SERVER-48569 Add ConflictingOperationInProgress as acceptable error code to stepDown in validateCollectionsCallback
SERVER-48657 Use evergreen module to control signal processing in perf projects
SERVER-48891 nullptr dereference on ViewCatalog in reIndex when Database does not exist
SERVER-48907 Allow users to patch test changes to linkbench/linkbench2 using evergreen set-module
SERVER-49007 Roundtrip registration id in metrics response in mock_http_server.py
SERVER-49071 Make ldap_fastest_host_selection.js tolerate missing LDAP servers in statistics
SERVER-49097 sys-perf builds differ from release builds
SERVER-49142 Validate correct field name in RoleName::parseFromBSON()
SERVER-49335 publish_packages should use barque API key
SERVER-49404 Enforce additional checks in $arrayToObject
SERVER-49690 Retry "CappedPositionLost" when searching for old oplog entries
SERVER-49704 txn_being_applied_to_secondary_cannot_be_killed.js should not allow elections
SERVER-50173 [v4.4] Remove explode_for_sort_collation.js from backports list of test suite sharding_multiversion
WT-6261 Turn off incremental backup rename testing
WT-6319 Fix for corrupted encrypted item: padded size less than actual size
WT-6480 Fix a bug where files without block modification information were repeatedly copied at each incremental backup
WT-6495 Refactor test_backup16.py

4.2 Changelog.css-134mg1q{-webkit-align-self:center;-ms-flex-item-align:center;align-self:center;padding:0 10px;visibility:hidden;}.css-6vrlzm{border-radius:0!important;display:initial!important;margin:initial!important;}.css-1l4s55v{margin-top:-175px;position:absolute;padding-bottom:2px;}

4.2.20 Changelog

Sharding

Aggregation

Internals

4.2.19 Changelog

Sharding

Query

Aggregation

Storage

Internals

4.2.18 Changelog

Sharding

Replication

Aggregation

Storage

Operations

Internals

4.2.17 Changelog

Storage

Internals

4.2.16 Changelog

Security

Sharding

Replication

Query

Build and Packaging

Internals

4.2.15 Changelog

Security

Sharding

Replication

Write Operations

Storage

Operations

Build and Packaging

Internals

4.2.14 Changelog

Sharding

Replication

Query

Storage

Operations

Build and Packaging

Internals

4.2.13 Changelog

Sharding

Replication

Query

Storage

Build and Packaging

Internals

4.2.12 Changelog

Sharding

Replication

Query

Aggregation

Storage

Build and Packaging

Internals

4.2.11 Changelog

Security

Sharding

Replication

Query

Write Operations

Aggregation

Storage

Operations

Build and Packaging

Internals

4.2.10 Changelog

Security

Sharding

Replication

Query

Aggregation

Operations

Build and Packaging

Internals

4.2 Changelog