Managing throttles for hosts

You can create, modify, and remove throttles for hosts by using the management GUI or the command-line interface.

Throttles are a mechanism to control the amount of resources that are used when the system is processing I/Os on a specific host or host cluster. If a throttle is defined, the system either processes the I/O, or delays the processing of the I/O to free resources for more critical I/O.

Using the management GUI

To create a new throttle for a specific host, complete these steps:
  1. In the management GUI, select Hosts > Hosts.
  2. Right-click a host or multiple hosts and select Edit Throttle....
  3. On the Edit Throttle page, enter values for the following throttles:
    Bandwidth Limit
    Enter the maximum amount of bandwidth the host can process before the system delays processing for this host. Click Create.
    IOPS Limit
    Enter the maximum I/O operations per second the host can process before the system delays processing for this host. Click Create.
To change an existing throttle, complete these steps:
  1. In the management GUI, select Hosts > Hosts.
  2. Right-click a host cluster and select Edit Throttle....
  3. On the Edit Throttle page, enter values for the following throttles:
    Bandwidth Limit
    Enter the maximum amount of bandwidth the host can process before the system delays processing for this host. Click Save.
    IOPS Limit
    Enter the maximum I/O operations per second the host can process before the system delays processing for this host. Click Save.
To remove throttles for a specific host, complete these steps:
  1. In the management GUI, select Hosts > Hosts.
  2. Right-click a host or multiple hosts and select Edit Throttle....
  3. On the Edit Throttle page, click Remove by the throttle that you want to delete.

Using the command-line interface

To create a new throttle for bandwidth and IOPS for a host with the command-line interface, enter the following command:
mkthrottle -type host -bandwidth bandwidth_limit_in_mb -iops iops_limit -host  host_id_or_host_name
where bandwidth_limit_in_mb is the maximum amount of bandwidth that the system can process for the specified host before the system delays processing of I/O for that host. The iops_limit is the maximum I/O operations per second that the system can process before the system delays processing for this host. The host_id_or_host_name is the ID or name of the host that the throttle applies to.
To change an existing throttle for the host, enter the following command:
chthrottle -type host -bandwidth bandwidth_limit_in_mb -iops iops_limit throttle_name_or_id
where bandwidth_limit_in_mb is the maximum amount of bandwidth that the system can process for the specified host before the system delays processing of I/O for that host. The iops_limit is the maximum I/O operations per second that the system can process before the system delays processing for this host. The throttle_id_or_name is the ID or name of the throttle that is being changed.
To remove a throttle for a host with the command-line interface, enter the following command:
rmthrottle throttle_name_or_id
where throttle_name_or_id is the ID or name of the throttle that is being removed.
Parent topic: Managing hosts