--- title: Index Service Metrics description: A list of the metrics provided by the Index Service. pubDate: 2026-08-18T04:50:45.818Z antora: editUrl: https://github.com/couchbase/docs-server/edit/release/8.0/modules/metrics-reference/pages/index-service-metrics.adoc xref: xref:server:metrics-reference:index-service-metrics.adoc[] --- [Consult the llms.txt file for a full list of contents](/llms.txt) [View original HTML](/server/current/metrics-reference/index-service-metrics.html) # Index Service Metrics > A list of the metrics provided by the Index Service. The following Index-Service metrics can be queried by means of the REST APIs described in [Statistics](../rest-api/rest-statistics.md). See [Index Service Cross Reference](index-service-metrics-cross-reference.md) if you are looking for a metric name you know from an alternative supported or legacy tool. > [!TIP] > * The x.y.z badge shows the Couchbase Server version the metric was added in. > * The type / unit badge shows shows the Prometheus [type](https://prometheus.io/docs/tutorials/understanding%5Fmetric%5Ftypes/) and [unit](https://prometheus.io/docs/practices/naming/#base-units) (if present). `index_avg_disk_bps` 7.2.0 gauge Sum of disk bytes written per second, of all indexes, located on this node `index_avg_drain_rate` 7.0.0 gauge Average number of documents indexed per second, for this index `index_avg_item_size` 7.0.0 gauge / bytes Average size of the indexed items, for this index `index_avg_mutation_rate` 7.2.0 gauge Sum of mutation rates of all indexes, located on this node `index_avg_resident_percent` 7.2.0 gauge Average resident percent across all indexes, located on this node `index_avg_scan_latency` 7.0.0 gauge / Nanoseconds Average latency observed by the index scans, for this index `index_cache_hits` 7.0.0 counter The number of times the required index page for both scan and mutations is found in memory, for this index `index_cache_misses` 7.0.0 counter The number of times the required index page for both scan and mutations is NOT found in memory, for this index `index_codebook_mem_usage` 7.7 counter / bytes Amount of memory used by codebook for this index, includes memory used for coarse codebook and quantization codebook `index_codebook_train_duration` 7.7 counter / Nanoseconds Amount of time spent in training the codebook, for this index `index_data_size` 7.0.0 gauge / bytes The approximate size of the valid uncompressed index data, for this index `index_data_size_on_disk` 7.0.0 gauge / bytes The size of the valid compressed index data, for this index `index_disk_bytes` 7.6.4 counter / bytes Number of bytes read from and written to disk, including insert, get, and delete operations `index_disk_size` 7.0.0 gauge / bytes Total disk space taken up by this index, after compression. This includes index data files, checkpoints etc. `index_frag_percent` 7.0.0 gauge Percentage of invalid index data, for this index `index_heap_in_use` 7.0.0 gauge / bytes Total heap memory in use by indexer process in the node `index_items_count` 7.0.0 gauge The actual number of items present in the latest index snapshot, for this index `index_log_space_on_disk` 7.0.0 gauge / bytes The size of the index data files - including garbage, for this index `index_memory_quota` 7.0.0 gauge / bytes Configured memory quota for the index service nodes `index_memory_rss` 7.2.0 gauge / bytes Resident set size of the indexer process, running on this node `index_memory_total_storage` 7.2.0 gauge / bytes Amount of memory used by the index memory allocator, on this node `index_memory_used` 7.0.0 gauge / bytes The memory used by this index `index_memory_used_storage` 7.2.0 gauge / bytes Amount of memory used by underlying index storage, on this node `index_memory_used_total` 7.0.0 gauge / bytes Total memory used by the indexer process `index_net_avg_scan_rate` 7.0.0 gauge Average index scan rate across all indexes, for this node `index_num_diverging_replica_indexes` 8.0.0 gauge Number of index partitions with diverging replica item counts. `index_num_docs_indexed` 7.0.0 counter Number of document updates (of type insert, modify, delete) observed by this index `index_num_docs_pending` 7.0.0 gauge Number of pending updates that are yet to be received by index service, for this index `index_num_docs_queued` 7.0.0 gauge Number of updates queued (but not yet processed) by index service, for this index `index_num_indexes` 7.2.0 gauge Total number of indexes, located on this node `index_num_items_flushed` 7.6.4 counter Number of documents written from memory to index storage `index_num_requests` 7.0.0 counter Number of scan requests received by the index service, for this index `index_num_rows_returned` 7.0.0 counter Number of rows/index entries returned as the scan result during index scans, for this index `index_num_rows_scanned` 7.0.0 counter Number of rows/index entries read during the index scans, for this index `index_num_storage_instances` 7.2.0 gauge Total number of storage instances, located on this node `index_partn_is_diverging_replica` 8.0.0 gauge Set to '1' if the index partition has diverging replica item counts `index_partn_items_count` 7.6.6 gauge The actual number of items present in the latest index snapshot, for this partition `index_raw_data_size` 7.0.0 gauge / bytes Encoded, uncompressed size of the index data, for this index `index_recs_in_mem` 7.0.0 gauge Number of index entries cached in memory, for this index `index_recs_on_disk` 7.0.0 gauge Number of index entries stored on disk, which are not cached in memory, for this index `index_resident_percent` 7.0.0 gauge Ratio of records in memory to total records, for this index `index_scan_bytes_read` 7.0.0 counter / bytes Number of bytes read from the index storage during index scans, for this index `index_scan_cache_hits` 8.0 counter Number of times the required index page for serving scan request is found in memory, for this index `index_scan_cache_misses` 8.0 counter Number of times the required index page for serving scan request is NOT found in memory, for this index `index_state` 7.6.6 gauge The current state of this index; CREATED: 0, READY: 1, INITIAL: 2, CATCHUP: 3, ACTIVE: 4, DELETED: 5, ERROR: 6, NIL: 7, SCHEDULED: 8, RECOVERED: 9\. Index is usable only in ACTIVE state `index_storage_avg_item_size` 7.6.0 gauge / bytes Ratio of total item size and total records `index_storage_bytes_incoming` 7.6.0 gauge / bytes Aggregated total of bytes that are added to the stores and intended to be written on disc `index_storage_bytes_written` 7.6.0 gauge / bytes Aggregated total of bytes written to the disc(data and recovery) `index_storage_cleaner_blk_read_bs` 7.6.0 gauge / bytes Total of number bytes read for cleaner log reads (both data and recovery) `index_storage_cleaner_num_reads` 7.6.0 gauge Total of number of cleaner log reads (both data and recovery) `index_storage_compression_ratio` 7.6.0 gauge / bytes Ratio of cumulative number of page bytes compressed and cumulative number of page bytes after compression `index_storage_current_quota` 7.6.0 gauge / bytes Plasma's internally active memory quota for this node. It is tuned by memtuner. `index_storage_heap_limit` 7.6.0 gauge / bytes Plasma's global heap limit for managed memory for this node `index_storage_hvi_blk_read_bs` 8.0.0 gauge Total number of bytes that were read from disk into memory `index_storage_hvi_blk_reads_bs_get` 8.0.0 gauge Total number of bytes that were read from disk into memory for index scans `index_storage_hvi_blk_reads_bs_lookup` 8.0.0 gauge Total number of bytes that were read from disk into memory for lookups `index_storage_hvi_buf_memused` 8.0.0 gauge Total Memory used by various reusable buffers `index_storage_hvi_bytes_incoming` 8.0.0 gauge Total number of bytes that were added to the stores and intended to be written to disk `index_storage_hvi_bytes_written` 8.0.0 gauge Total number of bytes that were written to disk `index_storage_hvi_compacts` 8.0.0 gauge Total count of compaction operations performed `index_storage_hvi_compression_ratio_avg` 8.0.0 gauge Ratio of data bytes to be compressed and data bytes after compression `index_storage_hvi_fragmentation` 8.0.0 gauge The fraction of garbage data present on disk `index_storage_hvi_memory_used` 8.0.0 gauge Total memory used by HVI indexes `index_storage_hvi_num_reads` 8.0.0 gauge Total number of times a disk block is read into memory `index_storage_hvi_num_reads_get` 8.0.0 gauge Total number of times a disk block was read into memory due to index scans `index_storage_hvi_num_reads_lookup` 8.0.0 gauge Total number of times a disk block was read into memory due to lookups `index_storage_hvi_resident_ratio` 8.0.0 gauge Ratio of cache mem used and cacheable size `index_storage_hvi_total_disk_size` 8.0.0 gauge Total disk usage in bytes `index_storage_hvi_total_used_size` 8.0.0 gauge Total number of disk bytes used. This size is eligible for cleanups in subsequent compactions. `index_storage_items_count` 7.6.0 gauge Aggregated number of items that are currently in the stores `index_storage_lookup_blk_reads_bs` 7.6.0 gauge / bytes Total number of bytes that were read from disc into memory for lookups `index_storage_lookup_num_reads` 7.6.0 gauge Total number of LSS lookups for looking up items from stores `index_storage_lss_blk_rdr_reads_bs` 7.6.0 gauge / bytes Total number of bytes that were read from disc into memory from the logs(both data and recovery) for index scans `index_storage_lss_blk_read_bs` 7.6.0 gauge / bytes Total number of bytes that were read from disc into memory from the logs(both data and recovery) `index_storage_lss_fragmentation` 7.6.0 gauge The fraction of garbage data present in the logs `index_storage_lss_num_reads` 7.6.0 gauge Total number of times an LSS(both data and recovery) block is read from disk into memory `index_storage_lss_used_space` 7.6.0 gauge / bytes Total number of bytes used by data and recovery logs `index_storage_memory_stats_size_page` 7.6.0 gauge / bytes Aggregated number of bytes of memory currently in use by Plasma for page records `index_storage_num_burst_visits` 7.6.0 gauge Aggregated total of pages visited during burst eviction `index_storage_num_evictable` 7.6.0 gauge Aggregated total of the number of pages can be compressed `index_storage_num_evicted` 7.6.0 gauge Aggregated total of the number of pages that were evicted and persisted to disc `index_storage_num_pages` 7.6.0 gauge Aggregated number of pages that are currently in use `index_storage_num_periodic_visits` 7.6.0 gauge Aggregated total of pages visited during periodic eviction `index_storage_purges` 7.6.0 gauge Aggregated number of times various pages are compacted due to the MVCCPurger being triggered `index_storage_reclaim_pending_global` 7.6.0 gauge / bytes Aggregated number of bytes across all plasma instances which have been freed but not yet returned to OS `index_storage_resident_ratio` 7.6.0 gauge Ratio of cached records and total records `index_storage_rlss_num_reads` 7.6.0 gauge Total number of times an LSS block was read into memory due to index scans `index_total_data_size` 7.2.0 gauge / bytes Sum of data size of all indexes, located on this node `index_total_disk_size` 7.2.0 gauge / bytes Sum of disk size of all indexes, located on this node `index_total_drain_rate` 7.2.0 gauge Sum of drain rate of all indexes, located on this node `index_total_mutation_queue_size` 7.0.0 gauge Total number of index updates queued in the mutation queues, on this node `index_total_pending_scans` 7.0.0 gauge Sum of number of pending scans across all indexes, located on this node `index_total_raw_data_size` 7.0.0 gauge / bytes Sum of encoded, uncompressed size of the index data across all indexes, located on this node `index_total_requests` 7.2.0 counter Sum of number of requests received by all indexes, located on this node `index_total_rows_returned` 7.2.0 counter Sum of number of rows returned during index scan across all indexes, located on this node `index_total_rows_scanned` 7.2.0 counter Sum of number of rows scanned during index scans across all indexes, located on this node `index_total_scan_duration` 7.0.0 counter / Nanoseconds Total time taken by the scans requests, for this index