9c74ecfd0f
When there are no options specified for lparstat, it is expected to give reports since LPAR(Logical Partition) boot. APP(Available Processor Pool) is an indicator of how many cores in the shared pool are free to use in Shared Processor LPAR(SPLPAR). APP is derived using pool_idle_time which is obtained using H_PIC call. The interval based reports show correct APP value while since boot report shows very high APP values. This happens because in that case APP is obtained by dividing pool idle time by LPAR uptime. Since pool idle time is reported by the PowerVM hypervisor since its boot, it need not align with LPAR boot. To fix that export boot pool idle time in lparcfg and powerpc-utils will use this info to derive APP as below for since boot reports. APP = (pool idle time - boot pool idle time) / (uptime * timebase) Results:: Observe APP values. ====================== Shared LPAR ================================ lparstat System Configuration type=Shared mode=Uncapped smt=8 lcpu=12 mem=15573440 kB cpus=37 ent=12.00 reboot stress-ng --cpu=$(nproc) -t 600 sleep 600 So in this case app is expected to close to 37-6=31. ====== 6.9-rc1 and lparstat 1.3.10 ============= %user %sys %wait %idle physc %entc lbusy app vcsw phint ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- 47.48 0.01 0.00 52.51 0.00 0.00 47.49 69099.72 541547 21 === With this patch and powerpc-utils patch to do the above equation === %user %sys %wait %idle physc %entc lbusy app vcsw phint ----- ----- ----- ----- ----- ----- ----- ----- ----- ----- 47.48 0.01 0.00 52.51 5.73 47.75 47.49 31.21 541753 21 ===================================================================== Note: physc, purr/idle purr being inaccurate is being handled in a separate patch in powerpc-utils tree. Signed-off-by: Shrikanth Hegde <sshegde@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://msgid.link/20240412092047.455483-2-sshegde@linux.ibm.com
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.