Technologies/PostgreSQL/postgresql.heap_blocks_read
PostgreSQLPostgreSQLMetric

postgresql.heap_blocks_read

Heap blocks read from disk
Dimensions:None
Available on:DatadogDatadog (1)Native (1)PrometheusPrometheus (1)
Interface Metrics (3)
DatadogDatadog
Enabled with `relations`. The number of disk blocks read from this table. This metric is tagged with db, schema, table.
Dimensions:None
Native
Number of disk blocks read from table
Dimensions:None
PrometheusPrometheus
Number of disk blocks read from this table
Dimensions:None
Sources
postgresql.heap_blocks_readgithub.com
heap_blks_readgithub.com
statio_user_tables_heap_blocks_readgithub.com

Technical Annotations (20)

Configuration Parameters (1)
fillfactorrecommended: lower than 100
controls space left on each page for HOT updates to stay on same page
CLI Commands (6)
EXPLAIN (ANALYZE, BUFFERS) SELECT ... WHERE x = ? ORDER BY y LIMIT n;diagnostic
CREATE INDEX ON table(filter_column, order_column);remediation
EXPLAIN (ANALYZE, BUFFERS) SELECT ...diagnostic
CREATE INDEX idx_orders_status_created ON orders (status, created_at DESC);remediation
EXPLAIN ANALYZEdiagnostic
CREATE INDEX CONCURRENTLY ON cities (country_code) INCLUDE (id, latitude, longitude);remediation
Technical References (13)
multi-column indexconceptIndex Scan BackwardconceptcardinalityconceptSeq ScanconceptEXPLAIN ANALYZEcomponentBuffers: shared readconceptHOT updatesconceptpg_repackcomponentpg_squeezecomponentcovering indexconceptIndex Only ScanconceptINCLUDEconceptHeap Fetchesconcept
Related Insights (4)
Inefficient sort-then-limit requires fetching all rows before sortingwarning
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Sequential scan on large table causes excessive disk reads and slow query executioncritical
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Data locality degradation causes excessive buffer reads over timewarning
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Covering indexes reduce heap access but require clean visibility mapinfo
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