This is an initial scheduler implementation for ZFS Local PV.
* adding scheduler as a configurable option
* adding volumeWeightedScheduler as scheduling logic
The volumeWeightedScheduler will go through all the nodes as per
topology information and it will pick the node which has less
volume provisioned in the given pool.
lets say there are 2 nodes node1 and node2 with below pool configuration :-
```
node1
|
|-----> pool1
| |
| |------> pvc1
| |------> pvc2
|-----> pool2
|------> pvc3
node2
|
|-----> pool1
| |
| |------> pvc4
|-----> pool2
|------> pvc5
|------> pvc6
```
So if application is using pool1 as shown in the below storage class, then ZFS driver will schedule it on node2 as it has one volume as compared to node1 which has 2 volumes in pool1.
```yaml
kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
name: openebs-zfspv
provisioner: zfs.csi.openebs.io
parameters:
blocksize: "4k"
compression: "on"
dedup: "on"
thinprovision: "yes"
poolname: "pool1"
```
So if application is using pool2 as shown in the below storage class, then ZFS driver will schedule it on node1 as it has one volume only as compared node2 which has 2 volumes in pool2.
```yaml
kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
name: openebs-zfspv
provisioner: zfs.csi.openebs.io
parameters:
blocksize: "4k"
compression: "on"
dedup: "on"
thinprovision: "yes"
poolname: "pool2"
```
In case of same number of volumes on all the nodes for the given pool, it can pick any node and schedule the PV on that.
Signed-off-by: Pawan <pawan@mayadata.io>
This PR adds support to allow the CSI driver to pick up a node matching the topology specified in the storage class. Admin can specify allowedTopologies in the StorageClass to specify the nodes where the zfs pools are setup
```yaml
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
name: openebs-zfspv
allowVolumeExpansion: true
parameters:
blocksize: "4k"
compression: "on"
dedup: "on"
thinprovision: "yes"
poolname: "zfspv-pool"
provisioner: zfs-localpv
volumeBindingMode: WaitForFirstConsumer
allowedTopologies:
- matchLabelExpressions:
- key: kubernetes.io/hostname
values:
- gke-zfspv-pawan-default-pool-c8929518-cgd4
- gke-zfspv-pawan-default-pool-c8929518-dxzc
```
Note: This PR picks up the first node from the list of nodes available.
Signed-off-by: Pawan <pawan@mayadata.io>
provisioning and deprovisioning of
the volumes on the node where zfs pool
has already been setup. Pool name and the volume
parameters has to be given in storage class
which will be used to provision the volume.
Signed-off-by: Pawan <pawan@mayadata.io>
