After a publisher flushes a batch of messages the batch is (obviously) not received immediately by the service. While the batch remains pending it potentially consumes memory resources in the client (and/or the service).
Some applications may have constraints on the number of bytes and/or messages they can tolerate in this pending state, and may prefer to block or reject messages.
[[["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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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 the \u003ccode\u003eMaxPendingBytesOption\u003c/code\u003e struct within the Google Cloud Pub/Sub C++ library, specifically detailing its functionality for managing the maximum size of pending messages.\u003c/p\u003e\n"],["\u003cp\u003eThe documentation lists various versions of the library, ranging from version 2.11.0 to the latest release candidate 2.37.0-rc, each with links to the \u003ccode\u003eMaxPendingBytesOption\u003c/code\u003e documentation for that specific version.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eMaxPendingBytesOption\u003c/code\u003e is used to define the limit on the memory resources consumed by pending batches of messages, allowing applications to manage memory usage.\u003c/p\u003e\n"],["\u003cp\u003eThis option allows applications to block or reject messages when the maximum number of pending bytes is reached due to constraints on memory and pending messages.\u003c/p\u003e\n"],["\u003cp\u003e\u003ccode\u003eMaxPendingBytesOption\u003c/code\u003e is an alias of \u003ccode\u003estd::size_t\u003c/code\u003e, indicating that it represents a size or count.\u003c/p\u003e\n"]]],[],null,[]]