timescale / timescaledb-tune

A tool for tuning TimescaleDB for better performance by adjusting settings to match your system's CPU and memory resources.
https://www.timescale.com/
Apache License 2.0
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Index scan is not happening on tables in data nodes in multi node architecture #119

Open srkanthn opened 1 year ago

srkanthn commented 1 year ago

I have a 2 server Database setup with timescale installed, one server has 1 access node and another server has 2 data nodes.

I have a query that joins tables in the access node and data node and I am trying to fetch a few million rows over a few days range. The query takes 20 minutes to run and I observed Custom Scan/Data Node scan is happening instead of Index Scan. We ingest more than a million rows every 5 minutes (40GB per day)

Example: -> Custom Scan (AsyncAppend) (cost=101.33..35936027.84 rows=29464 width=24) (actual time=428.564..5473.172 rows=7254167 loops=1)

I would like to know if this is a limitation of Timescale DB or I am missing something.