MapR Cache Metrics

Every 10 seconds, the collectd service uses a MapR plugin to gather the following MapR-FS cache metrics on each node in the cluster.

Name Description
mapr.cache.lookups_data The number of cache lookups in the block cache.
mapr.cache.lookups_dir The number of cache lookups in the table LRU cache. The table LRU is used for storing internal B-Tree leaf pages.
mapr.cache.lookups_inode The number of cache lookups in the inode cache.
mapr.cache.lookups_largefile The number of cache lookups in the large file LRU cache. The large file LRU is used for storing files with size greater than 64K and also MapR-DB data pages.
mapr.cache.lookups_meta The number of cache lookups on the meta LRU cache. The meta LRU is used for storing internal B-Tree pages.
mapr.cache.lookups_smallfile The number of cache lookups on the small file LRU cache. This LRU is used for storing files with size less than 64K and also MapR-DB index pages.
mapr.cache.lookups_table The number of cache lookups in the table LRU cache. The table LRU is used for storing internal B-Tree leaf pages.
mapr.cache.misses_data The number of cache misses in the block cache.
mapr.cache.misses_dir The number of cache misses on the table LRU cache.
mapr.cache.misses_inode The number of cache misses in the inode cache.
mapr.cache.misses_largefile The number of cache misses on the large file LRU cache.
mapr.cache.misses_meta The number of cache misses on the meta LRU cache.
mapr.cache.misses_smallfile The number of cache misses on the small file LRU cache.
mapr.cache.misses_table The number of cache misses on the table LRU cache.