diff options
Diffstat (limited to 'src/mongo/s/transaction_router.h')
| -rw-r--r-- | src/mongo/s/transaction_router.h | 271 |
1 files changed, 136 insertions, 135 deletions
diff --git a/src/mongo/s/transaction_router.h b/src/mongo/s/transaction_router.h index 4d442f3a225..82e7498523a 100644 --- a/src/mongo/s/transaction_router.h +++ b/src/mongo/s/transaction_router.h @@ -215,78 +215,78 @@ public: } /** - * Starts a fresh transaction in this session or continue an existing one. Also cleans up the - * previous transaction state. - */ + * Starts a fresh transaction in this session or continue an existing one. Also cleans up + * the previous transaction state. + */ void beginOrContinueTxn(OperationContext* opCtx, TxnNumber txnNumber, TransactionActions action); /** - * Attaches the required transaction related fields for a request to be sent to the given - * shard. - * - * Calling this method has the following side effects: - * 1. Potentially selecting a coordinator. - * 2. Adding the shard to the list of participants. - * 3. Also append fields for first statements (ex. startTransaction, readConcern) - * if the shard was newly added to the list of participants. - */ + * Attaches the required transaction related fields for a request to be sent to the given + * shard. + * + * Calling this method has the following side effects: + * 1. Potentially selecting a coordinator. + * 2. Adding the shard to the list of participants. + * 3. Also append fields for first statements (ex. startTransaction, readConcern) + * if the shard was newly added to the list of participants. + */ BSONObj attachTxnFieldsIfNeeded(OperationContext* opCtx, const ShardId& shardId, const BSONObj& cmdObj); /** - * Processes the transaction metadata in the response from the participant if the response - * indicates the operation succeeded. - */ + * Processes the transaction metadata in the response from the participant if the response + * indicates the operation succeeded. + */ void processParticipantResponse(OperationContext* opCtx, const ShardId& shardId, const BSONObj& responseObj); /** - * Returns true if the current transaction can retry on a stale version error from a - * contacted shard. This is always true except for an error received by a write that is not - * the first overall statement in the sharded transaction. This is because the entire - * command will be retried, and shards that were not stale and are targeted again may - * incorrectly execute the command a second time. - * - * Note: Even if this method returns true, the retry attempt may still fail, e.g. if one of - * the shards that returned a stale version error was involved in a previously completed a - * statement for this transaction. - * - * TODO SERVER-37207: Change batch writes to retry only the failed writes in a batch, to - * allow retrying writes beyond the first overall statement. - */ + * Returns true if the current transaction can retry on a stale version error from a + * contacted shard. This is always true except for an error received by a write that is not + * the first overall statement in the sharded transaction. This is because the entire + * command will be retried, and shards that were not stale and are targeted again may + * incorrectly execute the command a second time. + * + * Note: Even if this method returns true, the retry attempt may still fail, e.g. if one of + * the shards that returned a stale version error was involved in a previously completed a + * statement for this transaction. + * + * TODO SERVER-37207: Change batch writes to retry only the failed writes in a batch, to + * allow retrying writes beyond the first overall statement. + */ bool canContinueOnStaleShardOrDbError(StringData cmdName) const; /** - * Updates the transaction state to allow for a retry of the current command on a stale - * version error. This includes sending abortTransaction to all cleared participants. Will - * throw if the transaction cannot be continued. - */ + * Updates the transaction state to allow for a retry of the current command on a stale + * version error. This includes sending abortTransaction to all cleared participants. Will + * throw if the transaction cannot be continued. + */ void onStaleShardOrDbError(OperationContext* opCtx, StringData cmdName, const Status& errorStatus); /** - * Returns true if the current transaction can retry on a snapshot error. This is only true - * on the first command recevied for a transaction. - */ + * Returns true if the current transaction can retry on a snapshot error. This is only true + * on the first command recevied for a transaction. + */ bool canContinueOnSnapshotError() const; /** - * Resets the transaction state to allow for a retry attempt. This includes clearing all - * participants, clearing the coordinator, resetting the global read timestamp, and sending - * abortTransaction to all cleared participants. Will throw if the transaction cannot be - * continued. - */ + * Resets the transaction state to allow for a retry attempt. This includes clearing all + * participants, clearing the coordinator, resetting the global read timestamp, and sending + * abortTransaction to all cleared participants. Will throw if the transaction cannot be + * continued. + */ void onSnapshotError(OperationContext* opCtx, const Status& errorStatus); /** - * Updates the transaction tracking state to allow for a retry attempt on a view resolution - * error. This includes sending abortTransaction to all cleared participants. - */ + * Updates the transaction tracking state to allow for a retry attempt on a view resolution + * error. This includes sending abortTransaction to all cleared participants. + */ void onViewResolutionError(OperationContext* opCtx, const NamespaceString& nss); /** @@ -301,206 +301,207 @@ public: LogicalTime getSelectedAtClusterTime() const; /** - * Sets the atClusterTime for the current transaction to the latest time in the router's - * logical clock. Does nothing if the transaction does not have snapshot read concern or an - * atClusterTime has already been selected and cannot be changed. - */ + * Sets the atClusterTime for the current transaction to the latest time in the router's + * logical clock. Does nothing if the transaction does not have snapshot read concern or an + * atClusterTime has already been selected and cannot be changed. + */ void setDefaultAtClusterTime(OperationContext* opCtx); /** - * If a coordinator has been selected for the current transaction, returns its id. - */ + * If a coordinator has been selected for the current transaction, returns its id. + */ const boost::optional<ShardId>& getCoordinatorId() const; /** - * If a recovery shard has been selected for the current transaction, returns its id. - */ + * If a recovery shard has been selected for the current transaction, returns its id. + */ const boost::optional<ShardId>& getRecoveryShardId() const; /** - * Commits the transaction. - * - * For transactions that only did reads or only wrote to one shard, sends commit directly to - * the participants and returns the first error response or the last (success) response. - * - * For transactions that performed writes to multiple shards, hands off the participant list - * to the coordinator to do two-phase commit, and returns the coordinator's response. - */ + * Commits the transaction. + * + * For transactions that only did reads or only wrote to one shard, sends commit directly to + * the participants and returns the first error response or the last (success) response. + * + * For transactions that performed writes to multiple shards, hands off the participant list + * to the coordinator to do two-phase commit, and returns the coordinator's response. + */ BSONObj commitTransaction(OperationContext* opCtx, const boost::optional<TxnRecoveryToken>& recoveryToken); /** - * Sends abort to all participants. - * - * Returns the first error response or the last (success) response. - */ + * Sends abort to all participants. + * + * Returns the first error response or the last (success) response. + */ BSONObj abortTransaction(OperationContext* opCtx); /** - * Sends abort to all shards in the current participant list. Will retry on retryable errors, - * but ignores the responses from each shard. - */ + * Sends abort to all shards in the current participant list. Will retry on retryable + * errors, but ignores the responses from each shard. + */ void implicitlyAbortTransaction(OperationContext* opCtx, const Status& errorStatus); /** - * If a coordinator has been selected for this transaction already, constructs a recovery - * token, which can be used to resume commit or abort of the transaction from a different - * router. - */ + * If a coordinator has been selected for this transaction already, constructs a recovery + * token, which can be used to resume commit or abort of the transaction from a different + * router. + */ void appendRecoveryToken(BSONObjBuilder* builder) const; /** - * Returns a string with the active transaction's transaction number and logical session id - * (i.e. the transaction id). - */ + * Returns a string with the active transaction's transaction number and logical session id + * (i.e. the transaction id). + */ std::string txnIdToString() const; /** - * Returns the participant for this transaction or nullptr if the specified shard is not - * participant of this transaction. - */ + * Returns the participant for this transaction or nullptr if the specified shard is not + * participant of this transaction. + */ const Participant* getParticipant(const ShardId& shard); /** - * Returns the statement id of the latest received command for this transaction. - */ + * Returns the statement id of the latest received command for this transaction. + */ StmtId getLatestStmtId() const { return p().latestStmtId; } /** - * Returns a copy of the timing stats of the transaction router's active transaction. - */ + * Returns a copy of the timing stats of the transaction router's active transaction. + */ const TimingStats& getTimingStats() const { return o().timingStats; } private: /** - * Resets the router's state. Used when the router sees a new transaction for the first time. - * This is required because we don't create a new router object for each transaction, but - * instead reuse the same object across different transactions. - */ + * Resets the router's state. Used when the router sees a new transaction for the first + * time. This is required because we don't create a new router object for each transaction, + * but instead reuse the same object across different transactions. + */ void _resetRouterState(OperationContext* opCtx, const TxnNumber& txnNumber); /** - * Internal method for committing a transaction. Should only throw on failure to send commit. - */ + * Internal method for committing a transaction. Should only throw on failure to send + * commit. + */ BSONObj _commitTransaction(OperationContext* opCtx, const boost::optional<TxnRecoveryToken>& recoveryToken); /** - * Retrieves the transaction's outcome from the shard specified in the recovery token. - */ + * Retrieves the transaction's outcome from the shard specified in the recovery token. + */ BSONObj _commitWithRecoveryToken(OperationContext* opCtx, const TxnRecoveryToken& recoveryToken); /** - * Hands off coordinating a two-phase commit across all participants to the coordinator - * shard. - */ + * Hands off coordinating a two-phase commit across all participants to the coordinator + * shard. + */ BSONObj _handOffCommitToCoordinator(OperationContext* opCtx); /** - * Sets the given logical time as the atClusterTime for the transaction to be the greater of - * the given time and the user's afterClusterTime, if one was provided. - */ + * Sets the given logical time as the atClusterTime for the transaction to be the greater of + * the given time and the user's afterClusterTime, if one was provided. + */ void _setAtClusterTime(OperationContext* opCtx, const boost::optional<LogicalTime>& afterClusterTime, LogicalTime candidateTime); /** - * Throws NoSuchTransaction if the response from abortTransaction failed with a code other - * than NoSuchTransaction. Does not check for write concern errors. - */ + * Throws NoSuchTransaction if the response from abortTransaction failed with a code other + * than NoSuchTransaction. Does not check for write concern errors. + */ void _assertAbortStatusIsOkOrNoSuchTransaction( const AsyncRequestsSender::Response& response) const; /** - * If the transaction's read concern level is snapshot, asserts the participant's - * atClusterTime matches the transaction's. - */ + * If the transaction's read concern level is snapshot, asserts the participant's + * atClusterTime matches the transaction's. + */ void _verifyParticipantAtClusterTime(const Participant& participant); /** - * Removes all participants created during the current statement from the participant list - * and sends abortTransaction to each. Waits for all responses before returning. - */ + * Removes all participants created during the current statement from the participant list + * and sends abortTransaction to each. Waits for all responses before returning. + */ void _clearPendingParticipants(OperationContext* opCtx); /** - * Creates a new participant for the shard. - */ + * Creates a new participant for the shard. + */ TransactionRouter::Participant& _createParticipant(OperationContext* opCtx, const ShardId& shard); /** - * Sets the new readOnly value for the current participant on the shard. - */ + * Sets the new readOnly value for the current participant on the shard. + */ void _setReadOnlyForParticipant(OperationContext* opCtx, const ShardId& shard, const Participant::ReadOnly readOnly); /** - * Updates relevant metrics when a new transaction is begun. - */ + * Updates relevant metrics when a new transaction is begun. + */ void _onNewTransaction(OperationContext* opCtx); /** - * Updates relevant metrics when a router receives commit for a higher txnNumber than it has - * seen so far. - */ + * Updates relevant metrics when a router receives commit for a higher txnNumber than it has + * seen so far. + */ void _onBeginRecoveringDecision(OperationContext* opCtx); /** - * Updates relevant metrics when the router receives an explicit abort from the client. - */ + * Updates relevant metrics when the router receives an explicit abort from the client. + */ void _onExplicitAbort(OperationContext* opCtx); /** - * Updates relevant metrics when the router begins an implicit abort after an error. - */ + * Updates relevant metrics when the router begins an implicit abort after an error. + */ void _onImplicitAbort(OperationContext* opCtx, const Status& errorStatus); /** - * Updates relevant metrics when a transaction is about to begin commit. - */ + * Updates relevant metrics when a transaction is about to begin commit. + */ void _onStartCommit(WithLock wl, OperationContext* opCtx); /** - * Updates relevant metrics when a transaction receives a successful response for commit. - */ + * Updates relevant metrics when a transaction receives a successful response for commit. + */ void _onSuccessfulCommit(OperationContext* opCtx); /** - * Updates relevant metrics when commit receives a response with a non-retryable command - * error per the retryable writes specification. - */ + * Updates relevant metrics when commit receives a response with a non-retryable command + * error per the retryable writes specification. + */ void _onNonRetryableCommitError(OperationContext* opCtx, Status commitStatus); /** - * The first time this method is called it marks the transaction as over in the router's - * diagnostics and will log transaction information if its duration is over the global slowMS - * threshold or the transaction log componenet verbosity >= 1. Only meant to be called when - * the router definitively knows the transaction's outcome, e.g. it should not be invoked - * after a network error on commit. - */ + * The first time this method is called it marks the transaction as over in the router's + * diagnostics and will log transaction information if its duration is over the global + * slowMS threshold or the transaction log componenet verbosity >= 1. Only meant to be + * called when the router definitively knows the transaction's outcome, e.g. it should not + * be invoked after a network error on commit. + */ void _endTransactionTrackingIfNecessary(OperationContext* opCtx, TerminationCause terminationCause); /** - * Returns all participants created during the current statement. - */ + * Returns all participants created during the current statement. + */ std::vector<ShardId> _getPendingParticipants() const; /** - * Prints slow transaction information to the log. - */ + * Prints slow transaction information to the log. + */ void _logSlowTransaction(OperationContext* opCtx, TerminationCause terminationCause) const; /** - * Returns a string to be logged for slow transactions. - */ + * Returns a string to be logged for slow transactions. + */ std::string _transactionInfoForLog(OperationContext* opCtx, TerminationCause terminationCause) const; |