Technologies/MySQL/db.client.operation.duration

MySQLMetric

db.client.operation.duration

Database operation execution time

Dimensions:None

Technical Annotations (82)

Configuration Parameters (19)

iterator.chunk_sizerecommended: 500

batch size for processing annotated results without loading entire result set

pool_moderecommended: transaction

PgBouncer pooling mode - connection assigned per transaction then returned to pool

max_client_connrecommended: 500

Maximum number of client connections PgBouncer accepts

default_pool_sizerecommended: 25

Pool size should be 25-50% of PostgreSQL max_connections

server_idle_timeoutrecommended: 600

Seconds before idle server connection is closed

page_sizerecommended: 50

Default pagination size for list endpoints when client doesn't specify

statement_timeoutrecommended: 10000

PostgreSQL query timeout in milliseconds to kill runaway queries

DATABASES

Dictionary in settings.py containing database credentials and connection settings

DATABASES.default.ENGINErecommended: dj_db_conn_pool.backends.postgresql

pooling-aware backend required for connection pooling

DATABASES.default.CONN_MAX_AGErecommended: 0

let pool manage connections, not Django's per-request reuse

DATABASES.default.POOL_OPTIONS.POOL_SIZErecommended: 10

number of persistent connections in pool

DATABASES.default.POOL_OPTIONS.MAX_OVERFLOWrecommended: 5

extra connections allowed beyond pool size

CONN_MAX_AGErecommended: 0

Prevents persistent connections from timing out; set to 0 to disable connection pooling

wait_timeout

MySQL server-side timeout for idle connections; coordinate with CONN_MAX_AGE

duration_threshold_msrecommended: 100

Threshold for marking queries as slow in span attributes

transaction_duration_threshold_msrecommended: 1000

Threshold for slow transaction warning

NPLUSONE_DETECTOR.THRESHOLDrecommended: 5

Query repetition count before middleware reports potential N+1 issue

managerrecommended: FastCountManager

Replace default manager to enable count caching

django.db.backendsrecommended: DEBUG

Logger level for SQL query logging to detect N+1 patterns

Error Signatures (8)

timeout errorslog pattern

Connection pool exhaustedlog pattern

DatabaseErrorexception

no more connections allowed (max_client_conn)error code

query_wait_timeouterror code

connection failed: connection to server at "...", port 6432 failed: ERROR: no more connections allowed (max_client_conn)error code

OperationalError: MySQL server has gone awayexception

deadlockexception

CLI Commands (9)

python manage.py dbshelldiagnostic

EXPLAIN ANALYZEdiagnostic

SHOW PROCESSLISTdiagnostic

SELECT * FROM pg_stat_activitydiagnostic

from django.db import connection, reset_queries
reset_queries()
print(f"Total queries: {len(connection.queries)}")

diagnostic

SHOW POOLSmonitoring

EXPLAIN ANALYZE SELECT * FROM orders ORDER BY created_at DESC LIMIT 50 OFFSET 0;diagnostic

CREATE INDEX idx_orders_created_at ON orders(created_at DESC);remediation

SELECT split_part(query, 'WHERE', 2) AS sql, COUNT(*) AS count FROM pg_stat_activity WHERE datname = '...' GROUP BY query

diagnostic

Technical References (46)

prefetch_relatedcomponentPrefetchcomponentSeq Scanconceptmodels.IndexcomponentDjango Debug Toolbarcomponentannotate()componentCountcomponentSumcomponentselect_related()componentprefetch_related()componentdjango-debug-toolbarcomponentPgBouncercomponentmax_connectionscomponent.iterator()componentserver-side cursorsconceptchunk_sizecomponentpaginationconceptORMcomponentorders modelcomponentOrder.objects.all()componentIndex Scanconceptsettings.pyfile pathdj_db_conn_poolcomponentpg_stat_activitycomponentDatabaseConnectionMiddlewarecomponentMIDDLEWAREcomponentCONN_MAX_AGEcomponentQuerySetcomponentTracedCursorWrappercomponentdb.slow_querycomponenttransaction.atomiccomponenttraced_atomiccomponentEXPLAINcomponentselect_relatedcomponentForeignKeycomponentQuerySet.count()componentFastCountManagercomponentDjango admincomponentFastCountQuerySetcomponentSQL joinconceptmany-to-many relationshipsconceptreverse foreign keyconceptSubquery()componentOuterRef()componentDjango REST FrameworkcomponentDATABASEScomponent

Related Insights (37)

Prefetch loads millions of related objects causing memory explosionwarning

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Missing database indexes cause 30+ second query times in productionwarning

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Django app consumes 100% CPU from infinite loops or full table scanscritical

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Annotated querysets with aggregates load massive result sets into memorywarning

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N+1 query pattern executes one query per object for related recordscritical

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PostgreSQL connection count exceeds limits causing memory exhaustionwarning

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Server-side cursors with iterator() hold long transactions causing lock contentionwarning

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Unpaginated queries on large tables cause expensive operationswarning

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Infrastructure-only monitoring misses Django application failureswarning

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PostgreSQL query spike causing checkout latency during peak trafficcritical

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N+1 query pattern degrading Django response timewarning

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Unpaginated list endpoints cause outage at scalecritical

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Missing index on ORDER BY column causes full table scan despite paginationwarning

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Missing query timeout allows indefinite hangs and connection pool exhaustioncritical

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DatabaseError during query or transaction operationscritical

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Default Django backend causes connection overhead under loadwarning

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Django connections remain idle indefinitely despite CONN_MAX_AGE settingcritical

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MySQL connection timeout causes 'server has gone away' errors during traffic spikescritical

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Django ORM generates duplicate queries causing high query counts per pagewarning

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N+1 query problem multiplies database queries per itemwarning

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Slow database queries exceed 100ms thresholdwarning

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Transaction deadlocks cause transaction rollbackcritical

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Long transactions exceed 1 second durationwarning

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Unindexed queries perform full table scanswarning

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Missing composite indexes on multi-criteria filterswarning

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Excessive joins from deep select_related chainingwarning

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Missing index on foreign keys in large tableswarning

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N+1 queries cause exponential database load as data scaleswarning

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Django QuerySet.count() becomes O(n) bottleneck on tables with millions of rowswarning

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Django admin becomes unusable due to count() on every list page for large tablescritical

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N+1 queries cause sluggish performance and scalability issueswarning

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Foreign key access without select_related causes N+1 querieswarning

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Many-to-many or reverse foreign key access causes N+1 querieswarning

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Aggregating related data in loops causes N+1 querieswarning

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Complex per-record calculations cause N+1 querieswarning

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Per-request database connections cause API latency under loadwarning

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Database bottleneck causes response time spikes during high trafficwarning

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