Red Hat Training

A Red Hat training course is available for Red Hat Gluster Storage

2.2. Optimizing Virtual Machines On Red Hat Storage Volumes

The readahead mechanism is essential for guest sequential read performance on virtual machines. The virtual machine-tuned profile provides insufficient readahead. You can optimize the virtual machine performance by changing the multiply_disk_readahead 4 to multiply_disk_readahead 16. If you are running a Red Hat Enterprise Linux host, run the following commands to enable read-ahead.
  1. Install the Tune daemon
    Install the tuned daemon that tunes the system settings dynamically.
    # yum install tuned
  2. Edit the virtual-guest profile provided by the Tune daemon.
    Edit the /etc/tune-profiles/virtual-guest/ktune.sh
    Identify the line multiply_disk_readahead 4 and replace it with multiply_disk_readahead 16
  3. Apply the virtual-guest profile on the virtual machines
    Activate the updated profile with the command:
    # tuned-adm profile virtual-guest