diff mbox series

[v2] doc/bitbake-user-manual-ref-variables.rst: update pressure monitoring instructions

Message ID 20251127-update-bb-pressure-instructions-v2-1-11f994dc3ff9@bootlin.com
State New
Headers show
Series [v2] doc/bitbake-user-manual-ref-variables.rst: update pressure monitoring instructions | expand

Commit Message

Antonin Godard Nov. 27, 2025, 4:42 p.m. UTC
After commit d492bbf0503d ("knotty: Integrate PSI reporting into the
UI") on BitBake, the pressure information is no longer printed on the
console by default and has moved to its own log domain.

Update the BB_PRESSURE_* variable descriptions to show how to follow
these messages.

Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>
Signed-off-by: Antonin Godard <antonin.godard@bootlin.com>
---
Changes in v2:
- Suggested by Quentin (thanks!): Switch shell lexer to the console
  lexer, the output is rendered better.
- Link to v1: https://patch.msgid.link/20251127-update-bb-pressure-instructions-v1-1-36f69a25d4ef@bootlin.com
---
 .../bitbake-user-manual-ref-variables.rst          | 48 ++++++++++++++--------
 1 file changed, 30 insertions(+), 18 deletions(-)


---
base-commit: 6ee4df8ab58e0175b43106d8a6cbac1f6ab8d022
change-id: 20251127-update-bb-pressure-instructions-14ed447446aa
diff mbox series

Patch

diff --git a/doc/bitbake-user-manual/bitbake-user-manual-ref-variables.rst b/doc/bitbake-user-manual/bitbake-user-manual-ref-variables.rst
index 734c7858a2..c95583fa4b 100644
--- a/doc/bitbake-user-manual/bitbake-user-manual-ref-variables.rst
+++ b/doc/bitbake-user-manual/bitbake-user-manual-ref-variables.rst
@@ -579,14 +579,18 @@  overview of their function and contents.
 
       .. note::
 
-         You may see numerous messages printed by BitBake in case the
-         :term:`BB_PRESSURE_MAX_CPU` is too low::
+         You can track the pressure information while a build is running with:
 
-            Pressure status changed to CPU: True, IO: False, Mem: False (CPU: 1105.9/2.0, IO: 0.0/2.0, Mem: 0.0/2.0) - using 1/64 bitbake threads
+         .. code-block:: console
 
-         This means that the :term:`BB_PRESSURE_MAX_CPU` should be increased to
-         a reasonable value for limiting the CPU pressure on the system.
-         Monitor the varying value after ``CPU:`` above to set a sensible value.
+            $ tail -F tmp/log/cooker/<machine>/console-latest.log | grep "Pressure status changed"
+            NOTE: Pressure status changed to CPU: True, IO: False, Mem: False (CPU: 1105.9/2.0, IO: 0.0/2.0, Mem: 0.0/2.0) - using 1/64 bitbake threads
+            ...
+
+         If these messages are printed a lot, it means that the :term:`BB_PRESSURE_MAX_CPU`
+         should be increased to a reasonable value for limiting the CPU pressure
+         on the system. Monitor the varying value after ``CPU:`` above to set a
+         sensible value.
 
    :term:`BB_PRESSURE_MAX_IO`
       Specifies a maximum I/O pressure threshold, above which BitBake's
@@ -616,14 +620,18 @@  overview of their function and contents.
 
       .. note::
 
-         You may see numerous messages printed by BitBake in case the
-         :term:`BB_PRESSURE_MAX_IO` is too low::
+         You can track the pressure information while a build is running with:
+
+         .. code-block:: console
 
-            Pressure status changed to CPU: None, IO: True, Mem: False (CPU: 2236.0/None, IO: 153.6/2.0, Mem: 0.0/2.0) - using 19/64 bitbake threads
+            $ tail -F tmp/log/cooker/<machine>/console-latest.log | grep "Pressure status changed"
+            NOTE: Pressure status changed to CPU: None, IO: True, Mem: False (CPU: 2236.0/None, IO: 153.6/2.0, Mem: 0.0/2.0) - using 19/64 bitbake threads
+            ...
 
-         This means that the :term:`BB_PRESSURE_MAX_IO` should be increased to
-         a reasonable value for limiting the I/O pressure on the system.
-         Monitor the varying value after ``IO:`` above to set a sensible value.
+         If these messages are printed a lot, it means that the :term:`BB_PRESSURE_MAX_IO` 
+         should be increased to a reasonable value for limiting the I/O pressure
+         on the system. Monitor the varying value after ``IO:`` above to set a
+         sensible value.
 
    :term:`BB_PRESSURE_MAX_MEMORY`
       Specifies a maximum memory pressure threshold, above which BitBake's
@@ -655,14 +663,18 @@  overview of their function and contents.
 
       .. note::
 
-         You may see numerous messages printed by BitBake in case the
-         :term:`BB_PRESSURE_MAX_MEMORY` is too low::
+         You can track the pressure information while a build is running with:
+
+         .. code-block:: console
 
-            Pressure status changed to CPU: None, IO: False, Mem: True (CPU: 29.5/None, IO: 0.0/2.0, Mem: 2553.3/2.0) - using 17/64 bitbake threads
+            $ tail -F tmp/log/cooker/<machine>/console-latest.log | grep "Pressure status changed"
+            NOTE: Pressure status changed to CPU: None, IO: False, Mem: True (CPU: 29.5/None, IO: 0.0/2.0, Mem: 2553.3/2.0) - using 17/64 bitbake threads
+            ...
 
-         This means that the :term:`BB_PRESSURE_MAX_MEMORY` should be increased to
-         a reasonable value for limiting the memory pressure on the system.
-         Monitor the varying value after ``Mem:`` above to set a sensible value.
+         If these messages are printed a lot, it means that the :term:`BB_PRESSURE_MAX_MEMORY`
+         should be increased to a reasonable value for limiting the memory
+         pressure on the system. Monitor the varying value after ``Mem:`` above
+         to set a sensible value.
 
    :term:`BB_RUNFMT`
       Specifies the name of the executable script files (i.e. run files)