[[["容易理解","easyToUnderstand","thumb-up"],["確實解決了我的問題","solvedMyProblem","thumb-up"],["其他","otherUp","thumb-up"]],[["難以理解","hardToUnderstand","thumb-down"],["資訊或程式碼範例有誤","incorrectInformationOrSampleCode","thumb-down"],["缺少我需要的資訊/範例","missingTheInformationSamplesINeed","thumb-down"],["翻譯問題","translationIssue","thumb-down"],["其他","otherDown","thumb-down"]],["上次更新時間：2025-09-05 (世界標準時間)。"],[],[],null,["# About upgrading the Memcached version of an instance\n\nThis page describes how your Memorystore for Memcached instance behaves during a version\nupgrade operation, how an upgrade operation can affect your application, and\nwhen you should run an upgrade operation. To learn how to upgrade an instance's\nMemcached version, see [Upgrade the Memcached version of an instance](/memorystore/docs/memcached/upgrade-memcached-version).\n\nUpgrading an instance has performance and storage implications for your\napplication.\n\nBest practices for upgrading an instance's Memcached version\n------------------------------------------------------------\n\nUpgrade your instance during periods of low instance traffic to minimize the impact of the full cache flush caused by the upgrade operation. To learn how to monitor instance traffic, see [Monitor Memcached instances](/memorystore/docs/memcached/monitor-instances).\n\nVersion upgrade behavior\n------------------------\n\nThe Memcached instance undergoes a complete cache flush during a version upgrade operation. Multi-node\ninstances are partially available during the upgrade operation. You cannot downgrade the instance to an earlier version once it has been upgraded.\n\nAn upgrade operation also causes the nodes to undergo a short connection reset of a couple minutes, or less. Applications should incorporate retry logic in the code to be able to reconnect to the nodes. The discovery endpoint and memcached node endpoints remain the same.\n\nBecause of the short term connection break, there may be a small amount of stale or inconsistent data that didn't write or update to the cache for the short amount of time the Memcached node was unavailable."]]
