How does elasticsearch decide how many shards can be restored in parallel

I made a snapshot of an index with 24 shards. The index is of size 700g. When restoring, it restores 4 shards in parallel.

My cluster is a new cluster with only one machine w/o replica nodes. The machine is AWS c3.8xlarge with 32 vCPUs and 60G memory. I also followed How to speed up Elasticsearch recovery?.

When restoring, the memory usage is full. How does elastic search decide how many shards can be restored in parallel? I was wondering how I can tune my machines' hardware config to make restore faster. If my cluster has more machines, can the restoring speed be improved linearly?

I recall the restoration of snapshots using the recovery mechanism, which can be tuned through these cluster settings.

This topic was automatically closed 28 days after the last reply. New replies are no longer allowed.