catalog_meta_cache_statistics

Overview

catalog_meta_cache_statistics shows one row for each FE, External Catalog, metadata-cache engine, and cache entry visible to the current user. It includes cache configuration and Caffeine activity, together with the retained-memory limits, estimated usage, and admission rejections introduced in Doris 4.1.4.

Database

information_schema

Table Information

Column	Type	Description
FE_HOST	STRING	FE node that reports the row.
CATALOG_NAME	STRING	External Catalog name.
ENGINE_NAME	STRING	Metadata-cache engine, such as hive, iceberg, or paimon.
ENTRY_NAME	STRING	Cache entry within the engine.
EFFECTIVE_ENABLED	BOOLEAN	Whether the entry is currently effective after evaluating enable, TTL, capacity, and weight settings.
CONFIG_ENABLED	BOOLEAN	Configured enable value.
AUTO_REFRESH	BOOLEAN	Whether managed automatic refresh is enabled.
TTL_SECOND	BIGINT	Expiration time in seconds. -1 means no expiration and 0 disables the entry.
CAPACITY	BIGINT	Configured count capacity. With max-weight, it is not a simultaneous count limit, but 0 still disables the entry.
ESTIMATED_SIZE	BIGINT	Approximate number of cached mappings.
REQUEST_COUNT	BIGINT	Total cache lookup requests.
HIT_COUNT	BIGINT	Cache hits.
MISS_COUNT	BIGINT	Cache misses.
HIT_RATE	DOUBLE	Cache hit rate from 0.0 to 1.0.
LOAD_SUCCESS_COUNT	BIGINT	Successful cache loads.
LOAD_FAILURE_COUNT	BIGINT	Failed cache loads.
TOTAL_LOAD_TIME_MS	BIGINT	Total cache load time in milliseconds.
AVG_LOAD_PENALTY_MS	DOUBLE	Average load time in milliseconds.
EVICTION_COUNT	BIGINT	Number of Caffeine and explicit local-budget evictions.
EVICTION_RATE	DOUBLE	Ratio of EVICTION_COUNT to REQUEST_COUNT; 0 when there are no requests.
INVALIDATE_COUNT	BIGINT	Number of explicit invalidations.
LAST_LOAD_SUCCESS_TIME	STRING	Time of the most recent successful load.
LAST_LOAD_FAILURE_TIME	STRING	Time of the most recent failed load.
LAST_ERROR	STRING	Most recent load error; empty when none is recorded.
MAX_WEIGHT	BIGINT	Effective entry memory limit in bytes.
ESTIMATED_WEIGHT	BIGINT	Current reserved estimated weight of this entry in bytes.
WEIGHT_REJECT_COUNT	BIGINT	Cumulative number of cache admissions rejected by incomplete estimation or insufficient weight budget.
LAST_WEIGHT_REJECT_REASON	STRING	Most recent weight-admission rejection reason.

For entries without an applicable FE, Catalog, or entry memory limit, MAX_WEIGHT is -1 and ESTIMATED_WEIGHT is 0.

Weight columns have two kinds of time semantics:

• ESTIMATED_WEIGHT is a gauge. It reports the reservation at query time.
• WEIGHT_REJECT_COUNT and the other count columns are cumulative for the current cache instance. They restart from zero when the cache group is rebuilt after a Catalog property change or an FE restart.

The table does not retain historical samples. Sample it periodically if you need a trend.

Usage Example

Summarize the reservation of memory-governed entries per Catalog. This is usually the first query during an FE memory investigation:

SELECT fe_host, catalog_name,
       SUM(estimated_weight) AS estimated_weight,
       SUM(weight_reject_count) AS weight_reject_count
FROM information_schema.catalog_meta_cache_statistics
WHERE max_weight >= 0
GROUP BY fe_host, catalog_name
ORDER BY estimated_weight DESC;

Inspect memory-governed entries and their most recent admission result:

SELECT fe_host, catalog_name, engine_name, entry_name,
       max_weight, estimated_weight,
       weight_reject_count, last_weight_reject_reason
FROM information_schema.catalog_meta_cache_statistics
WHERE max_weight >= 0
ORDER BY fe_host, catalog_name, engine_name, entry_name;

Inspect cache effectiveness and load failures for one Catalog: Inspect cache effectiveness and load failures for one Catalog:

SELECT engine_name, entry_name, effective_enabled,
       estimated_size, request_count, hit_rate,
       load_failure_count, last_error
FROM information_schema.catalog_meta_cache_statistics
WHERE catalog_name = 'iceberg_ctl'
ORDER BY engine_name, entry_name;