fabiand

$ fallocate -l datafile.tmp
$ fio range_sync.fio  # good
$ fio range_sync.fio & sleep 1 ; dd if=/dev/zero of=datafile.tmp bs=1 seek=5 count=1 bs=1M conv=notrunc  # bad

Refs

• https://gitlab.com/nbdkit/nbdkit/-/blob/41b8c03cc244616667c471348d2057e72e719512/plugins/file/file.c#L123
• https://fio.readthedocs.io/en/latest/fio_doc.html#cmdoption-arg-sync_file_range

fabiand

# Cluster COnfiguration Operator

$ kubectl get platformconfigs
NAME              TYPE               PHASE               DRIFT
VirtHigherDensity     HigherDensity      Healthy             None
MultiCluster      MultiCluster       InProgress          None
HighPerformance   HigherPerformance  WaitingForApproval  None
HighAvailability  HighAvailability   Drifted             ...
CephFS            CephFS             Disabled            ...
CephFS            CephFS             Disabled            ...

fabiand

kind: HCOPlatformConfigurations
spec:
  platformConfiguration
  - profile: higherDensity
    customization: …
  - profile: highAvailability
  - profile: SDS <-- ADDED
status:
  condition:
  - type: ready

fabiand

# "Explicit swap"
# The user can explicitly request swap
kind: Pod
spec:
  resources
    requests:
      # This assumes separate resources for mem and swap
      # Set by user
      memory: 2G
      # Set by user

fabiand

- hosts: localhost
  tasks:
    - name: Create VM
      kubernetes.kubevirt.kubevirt_vm:
        state: present
        name: testvm
        namespace: default
        labels:
          app: test
        spec:

fabiand

$ ./virtctl-v0.50.0-rc.0-linux-amd64 
Available Commands:
  plug volume         add a volume to a running VM
  completion        generate the autocompletion script for the specified shell
  console           Connect to a console of a virtual machine instance.
  expose            Expose a virtual machine instance, virtual machine, or virtual machine instance replica set as a new service.
  guest fs            Return full list of filesystems available on the guest machine.
  guestfs           Start a shell into the libguestfs pod
  guest osinfo       Return guest agent info about operating system.
  help              Help about any command

fabiand

# virtctl is in your $PATH
# You are logged into a cluster
# Then the snippet below enables seamless ssh login.
# Usage `ssh [<user>@]<vmname>.<namespace>.ocp`
# "ocp" can be anything, for convenience replace with your cluster's base fqdn
host *.ocp
	ProxyCommand virtctl port-forward --stdio=true %h %p

fabiand

flowchart
    OCP --> AdminView
    OCP --> DevView

    subgraph Views
        DevView
        AdminView
    end
    

fabiand

flowchart
    qPlatform["Current platform?"]
    qBM["With Bare-Metal nodes?"]
    qAZ["Special AZ needs?"]

    to-UPI["Use UPI"]
    to-hypershift["Use Hypershift"]

 qPlatform -- UPI-none --> qBM

fabiand

# JUST TO BRAINSTORM

- name: Create a VM object from an inline definition
  vm.kubevirt.io:
    state: present
    name: my-vm
    namespace: my-namespace
    spec:
      instancetype:
        name: clarge