Using Perf-Counter Properties

The performance register access control feature enables you to get, set and unset a domain's access rights to certain groups of performance registers.

Use the ldm add-domain and ldm set-domain commands to specify a value for the perf-counters property. The new perf-counters property value will be recognized by the guest domain on the next reboot. If no perf-counters value is specified, the value is htstrand. See the ldm(8) man page.

You can specify the following values for the perf-counters property:

global

Grants the domain access to the global performance counters that its allocated resources can access. Only one domain at a time can have access to the global performance counters. You can specify this value alone or with either the strand or htstrand value.

strand

Grants the domain access to the strand performance counters that exist on the CPUs that are allocated to the domain. You cannot specify this value and the htstrand value together.

htstrand

Behaves the same as the strand value and enables instrumentation of hyperprivilege mode events on the CPUs that are allocated to the domain. You cannot specify this value and the strand value together.

To disable all access to any of the performance counters, specify perf-counters=.

If the hypervisor does not have the performance access capability, attempting to set the perf-counters property fails.

The ldm list -o domain and ldm list -e commands show the value of the perf-counters property. If the performance access capability is not supported, the perf-counters value is not shown in the output.

Example 15-11 Creating a Domain and Specifying Its Performance Register Access

Create the new ldg0 domain with access to the global register set:

primary# ldm add-domain perf-counters=global ldg0

Example 15-12 Specifying the Performance Register Access for a Domain

Specify that the ldg0 domain has access to the global and strand register sets:

primary# ldm set-domain perf-counters=global,strand ldg0

Example 15-13 Specifying that a Domain Does Not Have Access to Any Register Sets

Specify that the ldg0 domain does not have access to any of the register sets:

primary# ldm set-domain perf-counters= ldg0

Example 15-14 Viewing Performance Access Information

The following examples show how to view performance access information by using the ldm list -o domain command.

• The following ldm list -o domain command shows that the global and htstrand performance values are specified on the ldg0 domain:

  primary# ldm list -o domain ldg0
  NAME     STATE     FLAGS     UTIL
  NORM
  ldg0     active    -n----    0.0% 0.0%
  
  SOFTSTATE
  Solaris running
  
  UUID
      062200af-2de2-e05f-b271-f6200fd3eee3
  
  HOSTID
      0x84fb315d
  
  CONTROL
      failure-policy=ignore
      extended-mapin-space=on
      cpu-arch=native
      rc-add-policy=
      shutdown-group=15
  perf-counters=global,htstrand
  
  DEPENDENCY
      master=
  
  PPRIORITY    4000
  
  VARIABLES
      auto-boot?=false
      boot-device=/virtual-devices@100/channel-devices@200/disk@0:a
        /virtualdevices@100/channel@200/disk@0
      network-boot-arguments=dhcp,hostname=solaris,
        file=http://10.129.241.238:5555/cgibin/wanboot-cgi
      pm_boot_policy=disabled=0;ttfc=2000;ttmr=0;

• The following ldm list -p -o domain command shows the same information as in the previous example but in the parseable form:

  primary# ldm list -p -o domain ldg0
  VERSION 1.12
  DOMAIN|name=ldg0|state=active|flags=normal|util=|norm_util=
  UUID|uuid=4e8749b9-281b-e2b1-d0e2-ef4dc2ce5ce6
  HOSTID|hostid=0x84f97452
  CONTROL|failure-policy=reset|extended-mapin-space=on|cpu-arch=native|rc-add-policy=|
  shutdown-group=15|perf-counters=global,htstrand
  DEPENDENCY|master=
  VARIABLES
  |auto-boot?=false
  |boot-device=/virtual-devices@100/channel-devices@200/disk@0
  |pm_boot_policy=disabled=0;ttfc=2500000;ttmr=0;