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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 retained-memory limits, estimated usage, eviction weight, and admission rejections introduced in Doris 4.1.4.

Database

information_schema

Table Information

ColumnTypeDescription
FE_HOSTSTRINGFE node that reports the row.
CATALOG_NAMESTRINGExternal Catalog name.
ENGINE_NAMESTRINGMetadata-cache engine, such as hive, iceberg, or paimon.
ENTRY_NAMESTRINGCache entry within the engine.
EFFECTIVE_ENABLEDBOOLEANWhether the entry is currently effective after evaluating enable, TTL, capacity, and weight settings.
CONFIG_ENABLEDBOOLEANConfigured enable value.
AUTO_REFRESHBOOLEANWhether managed automatic refresh is enabled.
TTL_SECONDBIGINTExpiration time in seconds. -1 means no expiration and 0 disables the entry.
CAPACITYBIGINTConfigured count capacity. With max-weight, it is not a simultaneous count limit, but 0 still disables the entry.
ESTIMATED_SIZEBIGINTApproximate number of cached mappings.
REQUEST_COUNTBIGINTTotal cache lookup requests.
HIT_COUNTBIGINTCache hits.
MISS_COUNTBIGINTCache misses.
HIT_RATEDOUBLECache hit rate from 0.0 to 1.0.
LOAD_SUCCESS_COUNTBIGINTSuccessful cache loads.
LOAD_FAILURE_COUNTBIGINTFailed cache loads.
TOTAL_LOAD_TIME_MSBIGINTTotal cache load time in milliseconds.
AVG_LOAD_PENALTY_MSDOUBLEAverage load time in milliseconds.
EVICTION_COUNTBIGINTNumber of Caffeine and explicit local-budget evictions.
INVALIDATE_COUNTBIGINTNumber of explicit invalidations.
LAST_LOAD_SUCCESS_TIMESTRINGTime of the most recent successful load.
LAST_LOAD_FAILURE_TIMESTRINGTime of the most recent failed load.
LAST_ERRORSTRINGMost recent load error; empty when none is recorded.
WEIGHT_BOUNDEDBOOLEANWhether this entry is governed by an applicable FE, Catalog, or entry memory limit.
MAX_WEIGHTBIGINTEffective entry memory limit in bytes.
ESTIMATED_WEIGHTBIGINTCurrent reserved estimated weight of this entry in bytes.
EVICTION_WEIGHTBIGINTCumulative estimated bytes released by automatic and local-budget eviction.
WEIGHT_REJECT_COUNTBIGINTCumulative number of cache admissions rejected by incomplete estimation or insufficient weight budget.
CATALOG_MAX_WEIGHTBIGINTCatalog memory limit in bytes.
CATALOG_ESTIMATED_WEIGHTBIGINTCurrent reserved estimated weight across managed entries in this Catalog.
GLOBAL_MAX_WEIGHTBIGINTFE-wide external metadata-cache memory limit in bytes.
GLOBAL_ESTIMATED_WEIGHTBIGINTCurrent reserved estimated weight across managed external metadata caches on the FE.
LAST_WEIGHT_REJECT_REASONSTRINGMost recent weight-admission rejection reason.

For count-bounded entries or an unconfigured parent limit, weight-related numeric columns use -1 when the value is not applicable.

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;