Courier Fetch: shards failed

Question

Why do I get these warnings after adding more data to my elasticsearch? And the warnings are different every time I browse the dashboard.

\"Courier Fetch: 30 of 60 s

Answer 1

For me tuning the threadpool search queue_size solved the issue. I tried a number of other things and this is the one that solved it.

I added this to my elasticsearch.yml

threadpool.search.queue_size: 10000

and then restarted elasticsearch.

Reasoning... (from the docs)

A node holds several thread pools in order to improve how threads memory consumption are managed within a node. Many of these pools also have queues associated with them, which allow pending requests to be held instead of discarded.

and for search in particular...

For count/search operations. Defaults to fixed with a size of int((# of available_processors * 3) / 2) + 1, queue_size of 1000.

For more information you can refer to the elasticsearch docs here...

I had trouble finding this information so I hope this helps others!