When using formatted I/O operations (typically operator<<(std::istream&...) this option controls the size of the in-memory buffer kept before a chunk is uploaded. Note that GCS only accepts chunks in multiples of 256KiB, so this option is always rounded up to the next such multiple.
Applications seeking optimal performance for downloads should avoid formatted I/O, and prefer using std::istream::write(). This option has no effect in that case.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2026-01-14 UTC."],[],[]]