Important
MongoDB 9.1 Availability
MongoDB 9.1 is production ready and is being incrementally rolled out to MongoDB Atlas clusters that use the Latest Version With Auto Upgrades option.
Availability for the remainder of MongoDB Atlas, MongoDB Enterprise Advanced, and MongoDB Community is coming soon.
9.0.7 Changelog
Sharding
SERVER-135406 Disable change stream multiversion tests
Replication
SERVER-134723 Fix crash if sync source resolver fails to find sync source for catchup
SERVER-134972 Improve log message when failing to apply batch of oplog entries
SERVER-135598 [v9.0] Fix failing tests from revert of SERVER-113184
Build and Packaging
SERVER-135249 Prevent change streams metrics exceptions from blocking serverStatus completion
SERVER-135633 Fix flaky updateLookup test
SERVER-136184 Require release Evergreen distros when the Bazel build wrapper uses release configurations
SERVER-136464 Isolate server and crypt package artifacts
SERVER-136667 Move PPC64LE CI builds to ARM64 hosts
SERVER-137293 Remove maxTimeMS restrictions on PBRT tests
Internals
SERVER-95479 Allow skipping rebuilding indexes during startup on failed initial syncs
SERVER-109479 Core analysis task is not aware of the fallback download links for multiversion binaries/debug symbols
SERVER-123024 Remove devcontainer tests from 8.3 staging branch
SERVER-126814 $bucket on untracked viewless timeseries can optimize the pipeline on mongos before prepending $_internalUnpackBucket
SERVER-129387 Optimize $queryStats for top-k metrics.workingTimeMillis.sum sort + limit pattern
SERVER-129849 Fix mongod shutdown hang waiting for search task executor
SERVER-131338 Refactor resmoke.bzl to anticipate custom py_binary
SERVER-131339 Use custom py_binary for resmoke instead of py_test to anticipate coverage impl
SERVER-131654 Tolerate calling cmc without secondaryCheckMode for multiversion suites
SERVER-132098 Upgrade timelib and timezone data files to 2026e
SERVER-132514 Consolidate Evergreen retry setup and fix retries never applying
SERVER-132633 Retry replSetStepUp in remove_newly_added_field_after_finishing_initial_sync.js
SERVER-132823 Harden remaining FCV concurrency workload teardowns after SERVER-125400
SERVER-133744 Tolerate file shrinkage in SimulateCrash hook's copy_file
SERVER-133956 Support higher shard_count for resmoke_suite_test
SERVER-134003 Remove redundant _recipientCtx.getState() read in resharding recipient change-streams-monitor completion path
SERVER-134070 Release held intents when locks are yielded
SERVER-134081 Express user-index plan spins forever when an index entry references a missing record
SERVER-134356 Reduce SlotBasedStageBuilder::buildGroup stack frame and max number of DocumentSource stages pushed to SBE
SERVER-134400 Add adaptive retry to change_stream_future_start_time_new_shard
SERVER-134475 Avoid activate_version_tasks race in activate_task.py
SERVER-134485 QueuedAdmissionWithLargeMaxTimeMSSucceeds may start sleeping after mock clock is advanced, causing a hang
SERVER-134495 make keys_collection_non_deprioritizable.js less timing sensitive
SERVER-134519 Mongos may fail to populate CollectionUUIDMismatch properly if dbPrimary returns a different error
SERVER-134546 Fix flaky BloomFilterWithStringKeys unit test
SERVER-134555 Translate queries on an empty-string metaField instead of requiring a non-empty metaField
SERVER-134625 Enforce correct query shape output from extensions to support reparseability
SERVER-134664 maxEstimatedScanBytes query rejection is not logged at default verbosity
SERVER-134716 Consume Mothra teams via S3
SERVER-134954 Fix race in NetworkInterfaceTest.TimeoutDuringConnectionHandshake
SERVER-134991 Add completion log for chunk migration
SERVER-135001 TransactionCoordinator can log "errors" after single-shard transactions
SERVER-135196 Remove patch-only kernel 6.19 buildvariants (other than rseq-check)
SERVER-135202 Make gRPC concurrent connection unit tests use a larger timeout
SERVER-135206 $convert to binData fails on a document of exactly BSONObjMaxUserSize because RCString rejects the boundary size
SERVER-135348 rewrite TicketHolderTestTick.WaitForTicketDeadlineBetweenTimeoutWindows to make it not timing depe
SERVER-135517 Skip metadata consistency check if snapshot predates fcv change
SERVER-135564 Address hang in BlockingResultsMerger unit test
SERVER-135600 Queued operations should participate in query memory load shedding
SERVER-135619 Bump mongot-extension version to v2.0.7
SERVER-135621 Add context metadata to GenerateAndCheckPerfResults failures
SERVER-135622 Disable lookup unwind hash join
SERVER-135656 Add metrics for change streams shard-targeting V2 state machine, control events, and placement history
SERVER-135720 Disable mongor tests
SERVER-135732 [v9.0] Make internal_search_id_lookup_ddl_concurrency.js align with current behavior
SERVER-135803 Fix UnorderedTicketSemaphore timing out after a permit becomes available
SERVER-136032 Bump mongot-extension version to v2.0.8
SERVER-136123 transaction_aborted_under_cache_pressure.js still flakes after SERVER-135094 fix: assertion misses NoSuchTransaction outcome
SERVER-136176 Backport cross compile for zseries machines
SERVER-136195 Add test tags
SERVER-136302 Retain traverseF in SBE $elemMatch MatchFrames
SERVER-136318 timeseries_insert_mixed_schema_docs.js bucket count assertion can fail under stepdown + viewless timeseries FCV upgrade/downgrade
SERVER-136499 Rename task selection tags
SERVER-136502 Abandon IndexBuildsCoordinator::onStepUp if the stepup is abandoned
SERVER-136507 Path arrayness constraints are not re-checked on PlanExecutor restore
SERVER-136534 Add internalEnablePathArraynessTraverseFElision query execution knob
SERVER-136570 Add multiversion exclusion for timeseries_empty_metafield_write.js
SERVER-136595 Update PGO profiles
SERVER-136649 Convert a test-only RSTL call to IR
SERVER-136721 Fix race in TaskRunnerTest
SERVER-136923 Use target architecture in cross-compiled server buildInfo
SERVER-137011 Tighten skipping metadata consistency check only if snapshot has no authoritative shards enabled
SERVER-137027 ObservableMutex's Timer::getTime() performs a syscall on non-x86 and non-arm64 builds
SERVER-137085 Update PGO profiles
SERVER-137133 wait for resharding cleanup and replication before comparing magic restore dbhashes
SERVER-137256 retry connections when verifying repl dbhash
SERVER-138312 Require prebuilt cryptography wheels and sandbox Python build caches
9.0.4 Changelog
Sharding
SERVER-131327 checkMetadataConsistency may return MissingShardKeyIndex false positive when migrating the first chunk to a shard
SERVER-132059 Block new ShardServerCatalogCacheLoader loads from starting on Authoritative Shards
SERVER-132175 checkMetadataConsistency may return SnapshotUnavailable from failed internal snapshot read
SERVER-134453 The transition to CSRS test hook can fail to step up a new primary due to starvation from test writes
SERVER-134571 Avoid slow removeShard in *_with_balancer_and_config_transitions_and_add_remove_shard
Replication
SERVER-133198 Handle stale primary member data case in sync source selection
SERVER-135078 [v9.0] Revert SERVER-128221 add initialSyncWaitForSyncSourceLastStableRecoveryTs to tests
SERVER-135081 [v9.0] Revert SERVER-125964 Apply initial sync oplog entries from initiating set oplog entry if the set recently initiated
Query
SERVER-127745 Resharding recipient service deadlock on rapid stepdown then stepup
SERVER-132733 $out commit in replica set concurrent to viewless timeseries FCV upgrade may return NamespaceExists error
SERVER-134017 SBE $_internalSearchIdLookup tripwires on kNotHandled with no fallback
Storage
WiredTiger
WT-17366 Order the row-store internal page key against the reference's home page
WT-18069 [Reconciliation] unit-test-xsan: LeakSanitizer leak of checkpoint reconcile multi array (row-store internal page)
WT-18089 Data race in __wt_cursor_dhandle_incr_use
WT-18120 Prevent eviction walk starvation for a tree dominating cache usage
WT-18242 Add diagnostics when prepared update resolution fails to find a key
WT-18592 failed: compile on macos-14-arm64 [wiredtiger @ 13caa84a]
Operations
WT-18540 Recovery fails with EINVAL after salvaging leftover journal tail on macOS
Build and Packaging
SERVER-131869 Retry write conflicts when dropping unfinished indexes during startup recovery
SERVER-133399 Ignore hermetic-container generated paths
SERVER-133486 Stop mongod hanging in shutdown under TSAN
SERVER-133693 Retry on MaxTimeMSExpired in blockUntilIndexQueryable
SERVER-134025 Preserve primary build command for package provenance
SERVER-134580 Presign custom build delivery URLs for 7 days
SERVER-134698 Deliver custom builds to version-addressed paths with a manifest
WT-18279 Update SWIG Python typemaps to use Python 3 C API
Internals
SERVER-114161 Re-enable test findAndModify explain test case for legacy timeseries collections
SERVER-114507 $out targeting moved unsharded collection should create the new collection on the same shard
SERVER-120440 Documentation Updates Replica Set Write Block
SERVER-123695 waitAfterCommandFinishesExecution failPoint's activation count can be incremented multiple times per access
SERVER-125754 Reduce SessionRuntimeInfoMap lock contention
SERVER-125921 Sharded timeseries collMod can abort without releasing participant critical sections
SERVER-127486 Harden geo code against GeoColl inputs with strict-winding polygons
SERVER-127898 Retry CSRS demotion related InvalidOptions failures in replica_sets_transition_to_csrs suite
SERVER-127946 Renew all test certs for 7.x, 8.x, 9.x
SERVER-129223 Investigate calling _shardsvrCheckMetadataConsistencySecondaryParticipant on lagged secondaries
SERVER-130426 Investigate why allowChunkOperation flag need to be set on commitCollectionMetadataLocally()
SERVER-130807 Re-enable shard key index check on secondaries
SERVER-131102 Delayed secondaries throw InconsistentShardCatalogCollectionMetadata on initial sync suites
SERVER-131168 tassert 9690601 doesn't hold for CMC on secondaries
SERVER-131174 Skip query knob PBTs on checkMetadataConsistency
SERVER-131175 checkMetadataConsistency hook missing backgroundSessionCollectionDrop yml parameter in disagg passthrough suites
SERVER-131207 Improve resmoke_test parallelism in large bazel test invocations
SERVER-131259 Install query settings command hooks in crud_bm fixture
SERVER-131262 Populate Locker debugInfo with OperationContext state in getGlobalLockManager()->dump()
SERVER-131323 Exclude internalQueryPlannerUseMultiplannerForSingleSolutions from query knob correctness PBT and mark it test-only
SERVER-131329 Tag query_settings_knob_validation_pbt.js as config_shard_incompatible
SERVER-131396 Propagate stepdown data to CheckMetadataConsistencyInBackground for MalformedTimeseriesBucketsCollection skip
SERVER-131436 Make CMC on secondaries read at a consistent timestamp when comparing shard and global catalogs
SERVER-131441 Fix DDL fuzzer compilation
SERVER-131464 Change value for heartbeatIntervalMillis in jepsen
SERVER-131524 pqs_stage_memory_knob_spill.js flaky on debug/sanitizer variants due to forced $group spilling
SERVER-131526 Remove duplicate attribute from log line in metadata consistency util
SERVER-131531 Exclude query_settings_knob_validation_pbt from analyze_shard_key_jscore_passthrough
SERVER-131581 Up the heartbeatIntervalMillis in Antithesis fixture
SERVER-131591 Fix upload machinery for old style jepsen tests
SERVER-131625 Add Ubuntu 26.04 support for Server.
SERVER-131685 Tag max_time_ms.js as resource_intensive
SERVER-131779 Add linux the kernel 7.0.14 exemption for ubuntu
SERVER-131821 Shutdown the TracerProvider instead of just closing the tracer
SERVER-131913 Disabled general mirrored reads during targeted tests
SERVER-132037 Resolve bsoncolumn decoder discrepancy in handling 8609800
SERVER-132078 [test only] Add new parameter to control when chunk migrations are allowed to proceed when recipient PIT history may be lost
SERVER-132083 _shardsvrMoveRange should fail with a StaleConfig when targeting an old donor
SERVER-132096 Cap test span writes in span_telemetry_context_impl_test
SERVER-132121 Retry write conflicts during setFeatureCompatibilityVersion
SERVER-132128 Fix FCV gating on durable shard inconsistencies check in check metadata consistencies
SERVER-132216 set_fcv_prepared_transaction.js: do not call setFCV on a single shard
SERVER-132225 Don't set minSnapshotHistoryWindowInSeconds to zero on move_stale_mongos.js
SERVER-132274 Exclude trivially_empty_queries.js from add_remove shard suites
SERVER-132359 Bump db contrib tool version
SERVER-132360 spawn a ticket wait in runTicketWaitTimeoutTest not return within 60s
SERVER-132383 Inconsistent defaultClientBaseBackoffMillis/defaultClientMaxBackoffMillis crashes server via BackoffWithJitter invariant
SERVER-132392 Strip migrationRecipientPITHistoryToPreserveInSecs from multiversion binaries that predate it
SERVER-132425 Lower block_replica_set_writes.js total runtime
SERVER-132440 Otel metrics and traces shutdown is not thread-safe
SERVER-132483 Extract non casual-consistent commands from timeseries_reads_setFCV.js
SERVER-132511 Add requires_large_host tag to compile_mongor
SERVER-132566 Fix NetworkInterfaceMock cancellation race that can hang transaction coordinator tests
SERVER-132638 count with limit 0 fails on a view but works on a collection
SERVER-132641 Two jstests from SERVER-128128 are flaky on transient routing errors
SERVER-132654 Make BeginOperationRollsBackOnPersistFailure more robust
SERVER-132667 Antithesis image build fails cloning 10gen/QA because the GitHub token expires during the build
SERVER-132706 Reduce concurrency on aubsan variants of replica_sets_reconfig_kill_stepdown_terminate_jscore_passthrough
SERVER-132726 moveChunk should not return InterruptedDueToReplStateChange from a healthy primary
SERVER-132736 transaction_aborted_under_cache_pressure.js leaks sessions at teardown and the cache-pressure detector rarely fires under WT-18120's improved eviction
SERVER-132752 Authoritative DDLs may commit to config.shard.catalog.chunks before its indexes are created
SERVER-132756 Relax egress metrics counter equality assertion in auth_client_metrics.js
SERVER-132777 QueuedAdmissionWithLargeMaxTimeMSSucceeds is racy
SERVER-132797 Ongoing migration errors added as an acceptable error in move_chunk_errors.js
SERVER-132806 checkMetadataConsistency reports spurious CollectionOptionsMismatch during a collMod on a sharded timeseries collection
SERVER-132813 exactCE hangs for $changeStream
SERVER-132817 [v9.0] Enable search_two_shard_memory_tracking_disabled.js on hybrid search disabled
SERVER-132857 Adapt kernel compatiblity error message to new known fixed versions
SERVER-132906 Improve handling of migrationRecipientPITHistoryToPreserveInSecs
SERVER-132922 WaitForTicketDeadlineBetweenTimeoutWindows unit test timing issue under stress
SERVER-133021 authoritative_collection_metadata_vs_ddls doesn't wait for replication in a test
SERVER-133049 Map "last-patch" to fcvConstants.latest instead of shellVersion() in MongoRunner.binVersionSubs
SERVER-133061 Make range_deletion_maxkey_guard.js more robust
SERVER-133067 ReshardingCoordinator StepDownStepUpEachTransition test can deadlock itself
SERVER-133148 Avoid using semi-initialized opCtx when retrying getMores
SERVER-133171 Fix core analysis for when file name has a space
SERVER-133182 Disable bulk_write_getMore.js in sharding upgrade/downgrade suites with unsharded collections
SERVER-133218 Fix chained-replication hang in check_metadata_consistency collMod test check_metadata_consistency_collmod_frozen_chunk_operations.js
SERVER-133231 Fix read_pref_cmd.js to wait for replica set before running profile
SERVER-133233 index_killop_after_stepdown.js checks the index is built on the stepped-down node before the new primary's commitIndexBuild has replicated to it
SERVER-133277 Make add_shard_block_setFCV.js a no passthrough test
SERVER-133278 Disable fsyncLock tests in sharding CSRS stepdown suites
SERVER-133295 Rebuild tests with debug info from resmoke_suite_test result tasks
SERVER-133298 Drop redundant bazel cquery from burn-in end-to-end test
SERVER-133366 Increase instance size of rhel8-debug-aubsan-roll-back-incremental-feature-flags variant
SERVER-133367 Collmod usages of checkAllowMigrationsOnConfigServer can leave chunk operations disabled on shards
SERVER-133431 Retry CheckReplDBHash on transient legacy timeseries buckets access failures
SERVER-133518 StepUp hangs when a stale in-memory chunk operation blocks recovery of a persisted recipient
SERVER-133530 Sort records in ClusteredRecordStore unit test
SERVER-133558 Make SessionCatalog::KillToken RAII so a dropped kill token cannot wedge a session
SERVER-133587 Prevent StaleConfig error in placement_conflict_time.js
SERVER-133591 cbr_shard_filter.js fails when featureFlagGetExecutorDeferredEngineChoice is off because an empty shard triggers zero-CE fallback to multiplanning
SERVER-133614 Timeseries catalog helpers pass boost::none instead of the open snapshot's read timestamp to establishConsistentCollection
SERVER-133659 Allow updating allowDeletions on an active replica set write block
SERVER-133661 Add change stream updateLookup test coverage for clustered collections
SERVER-133672 Raise defaultClientMaxRetryAttempts in sharding_csrs_continuous_config_stepdown
SERVER-133690 Delete multi_statement_write_aborts_on_failover.js
SERVER-133696 Use $count instead of $out in agg_match.js
SERVER-133733 Add metric for RSWB reporting if deletes are blocked or allowed
SERVER-133745 Avoid checkLogEntryRWC to match Slow in-progress query logs that lack applied writeConcern.w
SERVER-133749 Ensure that the priority port is listening before running tests in priority_port_metrics.js
SERVER-133787 Update PGO profiles
SERVER-133803 primary_casts_vote_on_stepdown.js fails: assert.eq expected term N+1, got N+2
SERVER-133806 Check CS in chunk operation coordinators
SERVER-133858 Some MigrationBlockingOperationCoordinatorV2Test cases are racy
SERVER-133890 Run with_mongot_extension suites under {A,UB}SAN
SERVER-133911 Create and include Jira ticket in pull request title for MONGO_VERSION bump PRs
SERVER-133947 Restore the previous RSWB allowDeletions configuration when an in-place update rolls back
SERVER-133979 Anchor the libzstd TSAN suppression
SERVER-133988 Deadlock between resharding initialization, chunk migration commit, and setFCV
SERVER-134011 grpc_core_test fails spuriously when server fails to bind
SERVER-134077 Query stats supplemental metrics are only recorded when the initial batch exhausts the cursor
SERVER-134080 Support non-scalar _id lookups in SbeSingleDocumentLookupExecutor
SERVER-134082 Initialize the Python venv before applying custom build version overrides
SERVER-134104 ShardsvrDropDatabaseParticipantCommand strips the mayBypassWriteBlocking flag
SERVER-134109 Update PGO profiles
SERVER-134189 Release artifact tasks fail before checkout with custom build version overrides
SERVER-134438 MovePrimary stucks if the target is a draining node
SERVER-134439 Fix $graphLookup $_internalFromPipeline serialization asymmetry
SERVER-134533 Starting shard draining during movePrimary can cause metadata inconsistencies
SERVER-134581 Harden updateLookup and $_internalSearchIdLookup enrichment testing with per-engine lookup metrics
SERVER-134686 $_internalSearchIdLookup reports orphaned documents on _id-sharded collections (shard filter dropped for shard-local lookups)
SERVER-134714 Fix potential std::terminate in MovePrimaryCoordinator
SERVER-134719 Update performance microbenchmark thresholds
SERVER-134745 Sharded local change-stream updateLookup fails getMore with NamespaceNotFound when the database was dropped, instead of a null fullDocument
SERVER-134768 Reduce buildSort stack frame size to reduce likelihood of stack overflow with some PGO profiles
SERVER-134772 Fix sharded_search_network_interruption.js against a real mongot
SERVER-134811 [v9.0] Revert ARM64 PGO and BOLT profile data to the Aug 24 refresh
SERVER-134952 updateLookup change stream returns null fullDocument for updates on a shard-local/uncataloged database
SERVER-135507 Exclude agg_lookup_in_txn from running in step-down suites
SERVER-135529 [v9.0] Revert SERVER-128307
SERVER-135622 Disable lookup unwind hash join
SERVER-136272 Docker image fails to boot on Ubuntu 26.04.1 LTS, on 9.0.x and 8.3.x but not 8.2.
WT-15887 test_prepare_hs03 assert_ckpt_matches fails
WT-17597 [Checkpoint] test_timestamp_abort_stress: crash in __ckpt_valid_blk_mods during checkpoint metadata load
WT-18362 Checkpoint and stat logging reopen handles closed in parallel by sweep
9.0.2 Changelog
Replication
SERVER-135076 [v9.0] Revert SERVER-127512 Fix index_build_killop_secondary_before_commit for in-memory suite
SERVER-135077 [v9.0] Revert SERVER-128307 Fix hanging during initial sync in atlas_initialsync_workflows.js
SERVER-135079 [v9.0] Revert SERVER-128583 Fix flakiness in resync_majority_member.js
SERVER-135080 [v9.0] Revert SERVER-125965 Wait for stable timestamp to advance in initial sync
Storage
WiredTiger
WT-17366 Order the row-store internal page key against the reference's home page
WT-18069 [Reconciliation] unit-test-xsan: LeakSanitizer leak of checkpoint reconcile multi array (row-store internal page)
WT-18120 Prevent eviction walk starvation for a tree dominating cache usage
WT-18242 Add diagnostics when prepared update resolution fails to find a key
Build and Packaging
WT-18279 Update SWIG Python typemaps to use Python 3 C API
Internals
SERVER-107128 Define trace context propagation in OP_MSG
SERVER-129272 [Join Optimization] Join plan cache admin commands + FTDC metrics
SERVER-131787 Include debug symbols for tasks on rseq variants
SERVER-134438 MovePrimary stucks if the target is a draining node
SERVER-134714 Fix potential std::terminate in MovePrimaryCoordinator
WT-15887 test_prepare_hs03 assert_ckpt_matches fails
WT-18362 Checkpoint and stat logging reopen handles closed in parallel by sweep
WT-18474 Skip disaggregated storage scenarios in the Python suite on the 9.0 branch
9.0.1 Changelog
Query
SERVER-36681 Dotted path {$ne: null} against array of scalars returns incorrect results
Internals
SERVER-132101 fix release package testing regex
SERVER-134008 Avoid cryptography sdist during Poetry bootstrap on s390x and ppc64le
SERVER-134063 Shred collection validator constants during parsing
SERVER-134109 Update PGO profiles
SERVER-134189 Release artifact tasks fail before checkout with custom build version overrides