How to set cpu/memory resources requests and limits for SAS OpenSearch

[EyalGonen]

Hi experts,

I am looking for an example on how to set the cpu/memory resources requests and limits for SAS internal OpenSearch.

I found example files in sas-bases/examples/configure-elasticsearch/internal/topology but none seem to provide an example.

I also wonder what are the default values as I could not find them too.

[gwootton]

In my environment my sas-opendistro-default-0 pod has requests of 500m CPU/2G Memory and limits of 6 CPU/2G Memory.

The opendistro operator uses the heapsize settings from those topology examples to set the memory requests/limits.

You're correct there is no example available for modifying the CPU setting.

[EyalGonen]

Hi @gwootton 

Thanks. 

Do you know how the operator calculates the memory request/limit based on the defined heapsize in the topology YAMLs? 

Do you know how the operator calculates the cpu request/limit? Is there a way to control this? I want to place OpenSearch on a big machine and I want to set the cpu limit to a larger number. 

[gwootton · Accepted solution]

I changed my heapsize in the sas-opendistro custom resource to 3G and the memory requests and limits were changed to 6G, so this calculation appears to be heapsize x role count, as mine is a single-node topology so the node has both master and data roles.

$ k get po sas-opendistro-default-0 -o jsonpath='{.spec.containers[0].resources}'
{"limits":{"cpu":"6","memory":"2G"},"requests":{"cpu":"500m","memory":"2G"}}

$ k patch opendistrocluster sas-opendistro --type='json' -p='[{"op": "replace", "path": "/spec/nodes/0/heapsize","value":"3G"}]'

For CPU, I patched the custom resource path /spec/template/spec/containers/0/resources, and the values I set were what the stateful set had applied.

$ k patch opendistrocluster sas-opendistro --type='json' -p='[{"op": "replace", "path": "/spec/template/spec/containers/0/resources","value":{"requests":{"cpu":"300m"},"limits":{"cpu":"4"}}}]'

$ k delete sts sas-opendistro-default-0

$ k get po sas-opendistro-default-0 -o jsonpath='{.spec.containers[0].resources}'
{"limits":{"cpu":"4","memory":"6G"},"requests":{"cpu":"300m","memory":"6G"}}