Doc/Bdev/QoS: add the user information for the QoS on bdev section

This patch is to add the description of QoS (IOPS and bandwidth)
rate limits usage guide.

Change-Id: Ib351d89ee08ec131caa6f0037937b0dd86cd7dc1
Signed-off-by: GangCao <gang.cao@intel.com>
Reviewed-on: https://review.gerrithub.io/429432
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Chandler-Test-Pool: SPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Changpeng Liu <changpeng.liu@intel.com>
This commit is contained in:
GangCao 2018-10-15 17:11:57 -04:00 committed by Changpeng Liu
parent e66d09029b
commit 136160ad46

View File

@ -48,6 +48,10 @@ Example response
~~~
{
"num_blocks": 32768,
"assigned_rate_limits": {
"rw_ios_per_sec": 10000,
"rw_mbytes_per_sec": 20
},
"supported_io_types": {
"reset": true,
"nvme_admin": false,
@ -66,6 +70,17 @@ Example response
}
~~~
## set_bdev_qos_limit {#set_bdev_qos_limit}
Users can use the `set_bdev_qos_limit` RPC command to enable, adjust, and disable
rate limits on an existing bdev. Two types of rate limits are supported:
IOPS and bandwidth. The rate limits can be enabled, adjusted, and disabled at any
time for the specified bdev. The bdev name is a required parameter for this
RPC command and at least one of `rw_ios_per_sec` and `rw_mbytes_per_sec` must be
specified. When both rate limits are enabled, the first met limit will
take effect. The value 0 may be specified to disable the corresponding rate
limit. Users can run this command with `-h` or `--help` for more information.
## delete_bdev {#bdev_ug_delete_bdev}
To remove previously created bdev user can use `delete_bdev` RPC command.