# Altinity Expert Clickhouse Logs

> Analyze ClickHouse system log table health including TTL configuration, disk usage, freshness, and cleanup. Use for system log issues and TTL configuration.

- Skill: `altinity/altinity-expert-clickhouse-logs` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add altinity/altinity-expert-clickhouse-logs`
- Raw SKILL.md: https://api.skillmd.com/api/skills/altinity/altinity-expert-clickhouse-logs/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- License: Apache-2.0
- Author: altinity (https://skillmd.com/u/altinity)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/altinity/altinity-expert-clickhouse-logs

---


## Diagnostics

Run all queries from `checks.sql` in this skill's directory and analyze the results.

## TTL Recommendations

| Log Table | Recommended TTL | Notes |
|-----------|----------------|-------|
| query_log | 7-30 days | Balance debugging vs disk |
| query_thread_log | Disable or 3 days | Very verbose |
| part_log | 14-30 days | Important for RCA |
| trace_log | 3-7 days | Large, mostly for debugging |
| text_log | 7-14 days | Important for debugging |
| metric_log | 7-14 days | Useful for trending |
| asynchronous_metric_log | 7-14 days | Low volume |
| crash_log | 90+ days | Rare, keep longer |


## KB articles
- https://kb.altinity.com/altinity-kb-setup-and-maintenance/altinity-kb-system-tables-eat-my-disk/