[[["์ดํดํ๊ธฐ ์ฌ์","easyToUnderstand","thumb-up"],["๋ฌธ์ ๊ฐ ํด๊ฒฐ๋จ","solvedMyProblem","thumb-up"],["๊ธฐํ","otherUp","thumb-up"]],[["์ดํดํ๊ธฐ ์ด๋ ค์","hardToUnderstand","thumb-down"],["์๋ชป๋ ์ ๋ณด ๋๋ ์ํ ์ฝ๋","incorrectInformationOrSampleCode","thumb-down"],["ํ์ํ ์ ๋ณด/์ํ์ด ์์","missingTheInformationSamplesINeed","thumb-down"],["๋ฒ์ญ ๋ฌธ์ ","translationIssue","thumb-down"],["๊ธฐํ","otherDown","thumb-down"]],["์ต์ข ์ ๋ฐ์ดํธ: 2025-08-27(UTC)"],[[["\u003cp\u003eKey Visualizer divides row keys into 1,000 contiguous ranges called key buckets to report metrics, which are presented as averages or maximum values within each bucket.\u003c/p\u003e\n"],["\u003cp\u003eThe Activity metric, specifically the "Ops" metric, indicates the number of operations per row per minute, helping identify keys with higher request volumes.\u003c/p\u003e\n"],["\u003cp\u003eThe Warnings category includes metrics like "Read pressure index," "Write pressure index," and "Large rows" to highlight potential performance bottlenecks or data storage issues.\u003c/p\u003e\n"],["\u003cp\u003eReads and Writes categories provide metrics like "Read/Write CPU" and "Read/Write bytes client" to gauge resource utilization and data throughput per row.\u003c/p\u003e\n"],["\u003cp\u003eThe Performance category tracks latency for read and write operations with metrics like "Latency" and "Latency (max)" to evaluate operational speed, and the size category provides data on the amount of data stored and approximate number of rows in each key bucket.\u003c/p\u003e\n"]]],[],null,["# Key Visualizer metrics\n======================\n\nThis page describes the metrics that you can view in Key Visualizer heatmaps.\n\nMost Key Visualizer metrics represent a quantity per row. For example, the\n**Ops** metric measures the number of operations per row per minute.\n\n\nA Bigtable table can have trillions of rows, so it's not always practical to report\nmetrics for each individual row. Instead, Key Visualizer divides all of the row keys into 1,000\ncontiguous ranges, with roughly the same number of row keys in each range. These ranges are known\nas *key buckets*.\n\n\nKey Visualizer reports most metrics as averages over each key bucket, or as maximum values within\neach key bucket. For [**Warnings** metrics](/bigtable/docs/keyvis-metrics#warnings)\nand [**Performance** metrics](/bigtable/docs/keyvis-metrics#performance), Key\nVisualizer provides higher precision by reporting metrics for individual row keys or for specific\nkey ranges within the key bucket.\n\n\u003cbr /\u003e\n\n\nBefore you read this page, you should be familiar with the\n[overview of Key Visualizer](/bigtable/docs/keyvis-overview).\n\nActivity\n--------\n\nThe Activity category includes the **Ops** metric, which measures the number of\noperations per row per minute. This metric is roughly equal to the combined\nnumber of reads and writes and can indicate which keys received more requests at\na given time. Color indicates values relative to all observed values; therefore,\nyellow or white do not necessarily imply a hotspot.\n\nWarnings\n--------\n\nThe Warnings category includes metrics that identify possible performance issues\nwith a table.\nThis category includes the following metrics:\n\n- **Read pressure index**: An opaque, composite index for a row key or key range\n that incorporates the CPU utilization and latency for reads.\n\n\n This index reflects all of the values that were observed during a 15-minute interval. A value of 100\n or greater generally indicates poor performance for a key range. Poor performance can occur when you\n access a single row or a small range of rows very frequently, or when a row contains more than\n 256 MB of data.\n- **Write pressure index**: An opaque, composite index for a row key or key\n range that incorporates the CPU utilization and latency for writes.\n\n\n This index reflects all of the values that were observed during a 15-minute interval. A value of 100\n or greater generally indicates poor performance for a key range. Poor performance can occur when you\n access a single row or a small range of rows very frequently, or when a row contains more than\n 256 MB of data.\n- **Large rows**: The amount of data stored in rows that each contain more than\n 256 MB of data, or in key ranges with an average of more than\n 200 MB per row.\n\n Storing more than 256 MB of data per row can cause\n performance issues and read errors, and is not recommended.\n\n\nFor these metrics, when you move your cursor over the heatmap, Key Visualizer does not display\naggregated information for a key bucket. Instead, it displays information about specific row keys or\nkey ranges in your table, so that you can pinpoint the source of the issue.\n\nSee [Reviewing\nwarning metrics](/bigtable/docs/keyvis-getting-started#reviewing-warning-metrics) to learn how to view and act on these metrics.\n\nReads\n-----\n\nThe Reads category includes metrics related to reading data from a table.\n\nThis category includes the following metrics:\n\n- **Read CPU**: The average CPU utilization, expressed as the number of nodes that were used to read a row. Color indicates values relative to all observed values; therefore, yellow or white do not necessarily imply a hotspot.\n- **Read bytes client**: The number of bytes read by the client per minute per row. Color indicates values relative to all observed values; therefore, yellow or white do not necessarily imply a hotspot.\n\nWrites\n------\n\nThe Writes category includes metrics related to writing data to a table.\n\nThis category includes the following metrics:\n\n- **Write CPU**: The average CPU utilization, expressed as the number of nodes that were used to write a row. Color indicates values relative to all observed values; therefore, yellow or white do not necessarily imply a hotspot.\n- **Write bytes client**: The number of bytes written by the client per minute per row. Color indicates values relative to all observed values; therefore, yellow or white do not necessarily imply a hotspot.\n\nPerformance\n-----------\n\nThe Performance category includes metrics related to latency.\n\nThis category includes the following metrics:\n\n- **Latency**: The latency for read and write operations. One second (shown as orange) can be considered high.\n- **Latency (max)**: The maximum latency for reads or writes. One second (shown as orange) can be considered high.\n\n\nFor these metrics, when you move your cursor over the heatmap, Key Visualizer does not display\naggregated information for a key bucket. Instead, it displays information about specific row keys or\nkey ranges in your table, so that you can pinpoint the source of the issue.\n\nSize\n----\n\n- **Data stored:** The amount of data stored per row. This metric reflects the fact that Bigtable compresses your data when it is stored.\n- **Rows:** The approximate number of rows in each key bucket.\n\n The **Rows** heatmap typically appears mostly yellow. Horizontal stripes\n increasing in brightness from left to right, going from a darker color to\n a lighter color, indicate the addition of rows. Stripes that\n decrease in brightness from left to right indicate the deletion of rows.\n\n To see the total number of rows for a given key prefix, click on that\n prefix in the key hierarchy, then inspect the tooltips over the\n horizontal bar chart along the bottom.\n\nWhat's next\n-----------\n\n- [Get started with Key Visualizer](/bigtable/docs/keyvis-getting-started).\n- Learn [how Key Visualizer displays data in heatmaps](/bigtable/docs/keyvis-overview#heatmaps).\n- Find out [how to explore Key Visualizer heatmaps](/bigtable/docs/keyvis-exploring-heatmaps)."]]
