Case Heavy load : How we can search all search request cancellable to cancellation

[Beuhlet_Reseau (Newbie)]

Hello,

Maybe our cluster become unreacheable or with high latency.

I personally believe that tasks cancellation can be help to decrease load in cluster ?

I try this :

GET /_cat/thread_pool/search?v&h=node_name,name,active,rejected,completed
GET _tasks?actions=*search&cancellable=true

At the end, i search to retrieve all search task cancellable to cancellation during high load in cluster.

Thanks for help.

[warkolm (Mark Walkom)]

What version are you on?
What do you mean by unreachable?
What do your Elasticsearch logs show?
What does hot threads show?
What version are you one?
What is the output from _cluster/stats?pretty&human?

[Beuhlet_Reseau (Newbie)]

Hey Warkolm

I am the crazy man who works on ES 5.5.

What version are you on? 5.5
What do you mean by unreachable? I GET curl and no response
What do your Elasticsearch logs show? Full timeout between nodes communication
What does hot threads show? How i can give you this ?

Maybe during high load, the tasks cancellation can help to back on solid state (and no snake )

[Christian_Dahlqvist]

Cancellation of tasks is something that has been improved in recent versions and is still worked on, but as far as I recall this functionality was very limited in Elasticsearch 5.x.