Here’s the situation I had:
- Influxdb version: 1.4. Machine: Linux.
- The machine is fairly strong, with 4-core CPU, 16GB memory.
- 5-30 queries/second. Each query is same.
- Query: select COUNT(*) from Trades where time > 1512498660000000000 and time < 1512498660000000000 + 2h
- Only about 8000-18000 data points will be returned per query.
- Very high CPU usage.
- most of the queries didn’t across the shard.
- We stored data in ns.
What I observed:
- The query speed is irrelevant to the size of the result.
- On small machines, it OOM. On big machine, it used a lot of CPU.
Any insight for this weird situation? I think our workload is fairly small for a time series database.