To guarantee messages are received by the service in the same order that the application gives them to a publisher, the client library needs to wait until a batch of messages is successfully delivered before sending the next batch, otherwise batches may arrive out of order as there is no guarantee the same channel or network path is used for each batch.
For applications that do not care about message ordering, this can limit the throughput. Therefore, the behavior is disabled by default.
See Also
the documentation for the Publisher class for details.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14 UTC."],[[["\u003cp\u003eThe latest version available is 2.37.0-rc, with numerous prior versions dating back to 2.11.0 also accessible.\u003c/p\u003e\n"],["\u003cp\u003eThis page focuses on the \u003ccode\u003eMessageOrderingOption\u003c/code\u003e for Google Cloud Pub/Sub, which is found in the \u003ccode\u003egoogle::cloud::pubsub\u003c/code\u003e namespace across the different versions.\u003c/p\u003e\n"],["\u003cp\u003eMessage ordering guarantees that messages are received in the same order they are sent, which can decrease throughput as batches need to be delivered in full before the next is sent.\u003c/p\u003e\n"],["\u003cp\u003eMessage ordering behavior is disabled by default to avoid limiting throughput for applications that do not require this guarantee.\u003c/p\u003e\n"],["\u003cp\u003eMore details on message ordering can be found in the documentation for the \u003ccode\u003ePublisher\u003c/code\u003e class, with the \u003ccode\u003eMessageOrderingOption\u003c/code\u003e type alias being of type \u003ccode\u003ebool\u003c/code\u003e.\u003c/p\u003e\n"]]],[],null,[]]
