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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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\u003eThis webpage provides documentation for various versions of the \u003ccode\u003eMessageOrderingOption\u003c/code\u003e within the Google Cloud Pub/Sub C++ library, ranging from version 2.11.0 to the latest release candidate 2.37.0-rc.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eMessageOrderingOption\u003c/code\u003e is a feature that ensures messages are delivered to the service in the same order they were sent by the application.\u003c/p\u003e\n"],["\u003cp\u003eEnabling message ordering can reduce throughput because the client needs to confirm the delivery of one batch of messages before sending the next.\u003c/p\u003e\n"],["\u003cp\u003eMessage ordering is disabled by default to maximize throughput for applications that do not require it, and more details can be found in the documentation for the \u003ccode\u003ePublisher\u003c/code\u003e class.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eMessageOrderingOption\u003c/code\u003e is actually a type alias of \u003ccode\u003ebool\u003c/code\u003e.\u003c/p\u003e\n"]]],[],null,[]]
