Memory stats
This provides various memory-related stats including the stats from tcmalloc. Note that tcmalloc stats are not available on some operating systems (e.g., Windows) that do not support tcmalloc.
| Stat | Description |
|---|---|
| mem_used (deprecated) | Engine’s total memory usage |
| bytes | Engine’s total memory usage |
| ep_kv_size | Memory used to store item metadata, |
| keys and values, no matter the | |
| vbucket’s state. If an item’s value | |
| is ejected, this stat will be | |
| decremented by the size of the | |
| item’s value. | |
| ep_value_size | Memory used to store values for |
| resident keys | |
| ep_overhead | Extra memory used by transient data |
| like persistence queue, replication | |
| queues, checkpoints, etc | |
| ep_max_size | Max amount of data allowed in memory |
| ep_mem_low_wat | Low water mark for auto-evictions |
| ep_mem_high_wat | High water mark for auto-evictions |
| ep_oom_errors | Number of times unrecoverable OOMs |
| happened while processing operations | |
| ep_tmp_oom_errors | Number of times temporary OOMs |
| happened while processing operations | |
| ep_mem_tracker_enabled | If smart memory tracking is enabled |
| tcmalloc_allocated_bytes | Engine’s total memory usage reported |
| from tcmalloc | |
| tcmalloc_heap_size | Bytes of system memory reserved by |
| tcmalloc | |
| tcmalloc_free_bytes | Number of bytes in free, mapped |
| pages in page heap | |
| tcmalloc_unmapped_bytes | Number of bytes in free, unmapped |
| pages in page heap. These are bytes | |
| that have been released back to OS | |
| tcmalloc_max_thread_cache_bytes | A limit to how much memory TCMalloc |
| dedicates for small objects | |
| tcmalloc_current_thread_cache_bytes | A measure of some of the memory |
| TCMalloc is using for small objects |