[6/7] x86/resctrl: Update documentation with Sub-NUMA cluster changes

Message ID 20230126184157.27626-7-tony.luck@intel.com
State New
Headers
Series x86/resctrl: Add support for Sub-NUMA cluster (SNC) systems |

Commit Message

Luck, Tony Jan. 26, 2023, 6:41 p.m. UTC
  With Sub-NUMA Cluster mode enabled the scope of monitoring resources is
per-NODE instead of per-L3 cache. Suffices of directories with "L3" in
their name refer to Sun-NUMA nodes instead of L3 cache ids.

Signed-off-by: Tony Luck <tony.luck@intel.com>
---
 Documentation/x86/resctrl.rst | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)
  

Comments

James Morse Feb. 28, 2023, 5:14 p.m. UTC | #1
Hi Tony,

On 26/01/2023 18:41, Tony Luck wrote:
> With Sub-NUMA Cluster mode enabled the scope of monitoring resources is
> per-NODE instead of per-L3 cache. Suffices of directories with "L3" in

(Typo: Suffixes)

> their name refer to Sun-NUMA nodes instead of L3 cache ids.

(Typo: Sub-NUMA)


> diff --git a/Documentation/x86/resctrl.rst b/Documentation/x86/resctrl.rst
> index 71a531061e4e..9043a2d2f2d3 100644
> --- a/Documentation/x86/resctrl.rst
> +++ b/Documentation/x86/resctrl.rst
> @@ -167,6 +167,11 @@ with the following files:
>  		bytes) at which a previously used LLC_occupancy
>  		counter can be considered for re-use.
>  
> +"snc_ways":
> +                A value of "1" marks that SNC mode is disabled.

It would be good to expand the acronym the first time its used in the documentation.
This gives folk a few more characters to google!


> +                Values of "2" or "4" indicate how many NUMA
> +                nodes share an L3 cache.
> +
>  Finally, in the top level of the "info" directory there is a file
>  named "last_cmd_status". This is reset with every "command" issued
>  via the file system (making new directories or writing to any of the



Thanks,

James
  

Patch

diff --git a/Documentation/x86/resctrl.rst b/Documentation/x86/resctrl.rst
index 71a531061e4e..9043a2d2f2d3 100644
--- a/Documentation/x86/resctrl.rst
+++ b/Documentation/x86/resctrl.rst
@@ -167,6 +167,11 @@  with the following files:
 		bytes) at which a previously used LLC_occupancy
 		counter can be considered for re-use.
 
+"snc_ways":
+                A value of "1" marks that SNC mode is disabled.
+                Values of "2" or "4" indicate how many NUMA
+                nodes share an L3 cache.
+
 Finally, in the top level of the "info" directory there is a file
 named "last_cmd_status". This is reset with every "command" issued
 via the file system (making new directories or writing to any of the
@@ -254,9 +259,13 @@  When control is enabled all CTRL_MON groups will also contain:
 When monitoring is enabled all MON groups will also contain:
 
 "mon_data":
-	This contains a set of files organized by L3 domain and by
-	RDT event. E.g. on a system with two L3 domains there will
-	be subdirectories "mon_L3_00" and "mon_L3_01".	Each of these
+	This contains a set of files organized by L3 domain or by NUMA
+	node (depending on whether SNC mode is disabled or enabled
+	respectively) and by RDT event. E.g. on a system with SNC
+	mode disabled with two L3 domains there will be subdirectories
+	"mon_L3_00" and "mon_L3_01" the numerical suffix refers to the
+        L3 cache id.  With SNC enabled the directory names are the same,
+        but the numerical suffix refers to the node id.  Each of these
 	directories have one file per event (e.g. "llc_occupancy",
 	"mbm_total_bytes", and "mbm_local_bytes"). In a MON group these
 	files provide a read out of the current value of the event for