About #
PachW enables fine-grained control of where compaction and object-storage interaction occur by running storage tasks in a dedicated Kubernetes deployment. Users can configure PachW’s min and max replicas as well as define nodeSelectors, tolerations, and resource requests. Using PachW allows power users to save on costs by claiming fewer resources and running storage tasks on less expensive nodes.
If you are upgrading to 2.5.0+ for the first time and you wish to use PachW, you must calculate how many maxReplicas you need. By default, PachW is set to maxReplicas:1 — however, that is not sufficient for production runs.
maxReplicas #
You should set the maxReplicas value to at least match the number of pipeline replicas that you have. For high performance, we suggest taking the following approach:
number of pipelines * highest parallelism spec * 1.5 = maxReplicas
Let’s say you have 6 pipelines. One of these pipelines has a parallelism spec value of 6, and the rest are 5 or fewer.
6 * 6 * 1.5 = 54
minReplicas #
Workloads that constantly process storage and compaction tasks because they are committing rapidly may want to increase minReplicas to have instances on standby.
nodeSelectors #
Workloads that utilize GPUs and other expensive resources may want to add a node selector to scope PachW instances to less expensive nodes.
Values #
pachw:
inheritFromPachd: true # defaults below configuration options like 'resources' and 'tolerations' to values from pachd
maxReplicas: 1
minReplicas: 0
inSidecars: false
#tolerations: []
#affinity: {}
#nodeSelector: {}
pachw:
inheritFromPachd: true # defaults below configuration options like 'resources' and 'tolerations' to values from pachd
maxReplicas: 6 # set to match the number of pipeline replicas you have; sample formula: pipeline count * parallelism = target maxReplicas
minReplicas: 1
#tolerations: []
#affinity: {}
#nodeSelector: {}
#resources: # sets kubernetes resource configuration for pachw pods. If not defined, config from pachd is reused. We recommend defining resources when running pachw with a high value of maxReplicas (when formula is: target maxReplicas * 1.5).
#limits:
#cpu: "1"
#memory: "2G"
#requests:
#cpu: "1"
#memory: "2G"pachw:
inheritFromPachd: false # defaults below configuration options like 'resources' and 'tolerations' to values from pachd
maxReplicas: 6 # set to match the number of pipeline replicas you have; sample formula: pipeline count * parallelism = target maxReplicas
minReplicas: 1
#tolerations: []
#affinity: {}
#nodeSelector: {}
resources: # sets kubernetes resource configuration for pachw pods. If not defined, config from pachd is reused. We recommend defining resources when running pachw with a high value of maxReplicas (when formula is: target maxReplicas * 1.5).
limits:
cpu: "1"
memory: "2G"
requests:
cpu: "1"
memory: "2G"pachw:
inheritFromPachd: true # defaults below configuration options like 'resources' and 'tolerations' to values from pachd
inSidecars: true # processes storage related tasks in pipeline storage sidecars like version 2.4.2 or less.
maxReplicas: 1
#tolerations: []
#affinity: {}
#nodeSelector: {}