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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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\u003eThe content provides a detailed list of Google Cloud Pub/Sub C++ client library versions, ranging from the release candidate 2.37.0-rc down to version 2.11.0.\u003c/p\u003e\n"],["\u003cp\u003eEach version number in the list links to documentation for the \u003ccode\u003eMaxPendingMessagesOption\u003c/code\u003e struct, which controls the maximum number of messages that can be pending in the client.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eMaxPendingMessagesOption\u003c/code\u003e struct relates to managing resource usage by limiting the number of messages waiting to be processed by the service after a batch is flushed by a publisher.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003eMaxPendingMessagesOption\u003c/code\u003e struct is a type alias of \u003ccode\u003estd::size_t\u003c/code\u003e, indicating that it is an unsigned integer type suitable for representing sizes and counts.\u003c/p\u003e\n"]]],[],null,[]]
