القائمة
Diagnose ClickHouse RAM usage, OOM errors, memory pressure, and allocation patterns. Use for memory-related issues and out-of-memory errors.
التثبيت باستخدام Codex أو Claude انسخ هذا Prompt والصقه في Codex أو Claude أو مساعد آخر ليراجع صفحة Skill ويثبّتها لك.
استنادا إلى تصنيف SOC المهني
Read-only ClickHouse security audit expert for live or exported systems. Use when assessing ClickHouse security posture, reviewing users, roles, grants, settings profiles, row policies, table functions, external sources, table engines, executable UDFs, audit logs, named collections, password hash hygiene, SQL SECURITY DEFINER, impersonation, TLS/network exposure, Keeper/interserver security, encryption at rest, backups, the HTTP interface surface, cluster security, or version-specific ClickHouse security behavior. Diagnoses from SQL/system tables, supplied configuration files, query logs, access metadata, and ClickHouse/Altinity documentation.
Diagnose and resolve ClickHouse grant and authentication errors, especially after upgrades. Use when queries fail with ACCESS_DENIED/NOT_ENOUGH_PRIVILEGES, AUTHENTICATION_FAILED/WRONG_PASSWORD/REQUIRED_PASSWORD, or ON CLUSTER privilege errors; when system.* or INFORMATION_SCHEMA access is denied; or when grant behavior changes after version upgrades.
Analyze ClickHouse cache systems including mark cache, uncompressed cache, and query cache. Use for cache hit ratio issues and cache tuning.
Establishes the ClickHouse connection mode, cluster macro, and default log timeframe for diagnostics. Use first, before any other altinity-expert-clickhouse skill, to verify connectivity and set shared analysis rules.
Analyze ClickHouse external dictionaries including configuration, memory usage, reload status, and performance. Use for dictionary issues and load failures.
Analyze whether ClickHouse indexes (PRIMARY KEY, ORDER BY, skipping indexes, projections) are being used effectively for actual query patterns. Use when investigating index effectiveness, ORDER BY key design, query-to-index alignment, or when queries scan more data than expected.
| name | altinity-expert-clickhouse-memory |
| description | Diagnose ClickHouse RAM usage, OOM errors, memory pressure, and allocation patterns. Use for memory-related issues and out-of-memory errors. |
| license | Apache-2.0 |
Diagnose RAM usage, memory pressure, OOM risks, and memory allocation patterns.
Run all queries from checks.sql in this skill's directory and analyze the results.
Solutions:
max_bytes_before_external_group_bymax_threads pragma to limit parallelismSolutions:
max_bytes_in_joinjoin_algorithm = 'partial_merge' or 'auto'-- Always time-bound log queries
where event_date >= today() - 1
-- Limit results
limit 100
MemoryTracking - current tracked memoryMemoryResident - RSSOSMemoryTotal, OSMemoryFreeWithoutCached - system memory| Finding | Load Module | Reason |
|---|---|---|
| High merge memory | altinity-expert-clickhouse-merges | Analyze merge patterns |
| Large dictionaries | altinity-expert-clickhouse-dictionaries | Dictionary optimization |
| Cache too large | altinity-expert-clickhouse-caches | Cache sizing |
| PK memory high | altinity-expert-clickhouse-schema | ORDER BY optimization |
| Query OOMs | altinity-expert-clickhouse-reporting | Query optimization |
| Setting | Scope | Notes |
|---|---|---|
max_memory_usage | Query | Per-query limit |
max_memory_usage_for_user | User | Per-user aggregate |
max_server_memory_usage | Server | Global limit |
max_server_memory_usage_to_ram_ratio | Server | Auto-limit as % of RAM |
max_bytes_before_external_group_by | Query | Spill aggregation to disk |
max_bytes_in_join | Query | Spill join to disk |