[[["わかりやすい","easyToUnderstand","thumb-up"],["問題の解決に役立った","solvedMyProblem","thumb-up"],["その他","otherUp","thumb-up"]],[["わかりにくい","hardToUnderstand","thumb-down"],["情報またはサンプルコードが不正確","incorrectInformationOrSampleCode","thumb-down"],["必要な情報 / サンプルがない","missingTheInformationSamplesINeed","thumb-down"],["翻訳に関する問題","translationIssue","thumb-down"],["その他","otherDown","thumb-down"]],["最終更新日 2025-09-05 UTC。"],[],[],null,["# Key Visualizer metrics\n\nThis page describes the metrics that you can view in Key Visualizer heatmaps.\n\nMetrics\n-------\n\nKey Visualizer automtically captures and aggregates metrics about performance\nand resource usage for Spanner databases that have enabled it. All\nmetrics in Key Visualizer are normalized by the number of rows. This means\nthat the metric value inside a row range is the aggregated count divided by the\nnumber of rows inside the range.\n\nTime window granularity\n-----------------------\n\nSpanner Key Visualizer aggregates metrics at several different\ngranularities over time. The most recent data is aggregated at the finest\ngranularity, while earlier data is aggregated more coarsely.\n\nData retention and wipeout\n--------------------------\n\nSpanner stores key ranges and metrics in an internal metadata table\nas part of the user's database. Spanner Key Visualizer data retention\nis as follows:\n\n- Data that is collected every minute will be deleted after six hours.\n- Data that is collected every ten minutes will be deleted after four days.\n- Data that is collected every hour will be deleted after 28 days.\n\nKey Visualizer stores row key data in the metadata table. If your data retention\nrequirements aren't compatible with Key Visualizer's data retention schedule,\nyou can\n[disable Key Visualizer](/spanner/docs/key-visualizer/getting-started#enabling_key_visualizer).\n\nLimitations\n-----------\n\nThere are some situations in which new data might not be immediately available in\nKey Visualizer.\n\n- Storage and traffic statistics for newly created databases might not be available immediately.\n- Traffic statistics for newly inserted rows might be attributed to existing key ranges.\n\nWhat's next\n-----------\n\n- [Get started with Key Visualizer](/spanner/docs/key-visualizer/getting-started).\n- Learn [how Key Visualizer displays data in heatmaps](/spanner/docs/key-visualizer/exploring-heatmaps#heatmaps).\n- Find out [how to explore Key Visualizer heatmaps](/spanner/docs/key-visualizer/exploring-heatmaps)."]]