Abstract
On a running system with the realtime-virtual-host profile selected and the isolated_cores variable set to "4-N", the kernel command line contains the argument irqaffinity=0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15.
This argument should be irqaffinity=0,1,2,3.
Work around
Switching the variable to isolated_cores=4-15 corrects the problem
Investigation
The irqaffinity kernel cmdline argument is constructed using the non_isolated_cores tuned variable, which itself is defined as non_isolated_cores=${f:cpulist_invert:${isolated_cores}}.
The cpulist_invert function relies on the cpulist_unpack function, whose documentation does not mention the "N" value.
Note that this value is defined in the kernel command line documentation : https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html#cpu-lists
System
- Debian 13
- tuned version 2.25.1
I don't know whether this is a bug report or a feature request. Do you plan to add support for the "N" value ?
Abstract
On a running system with the
realtime-virtual-hostprofile selected and theisolated_coresvariable set to "4-N", the kernel command line contains the argumentirqaffinity=0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15.This argument should be
irqaffinity=0,1,2,3.Work around
Switching the variable to
isolated_cores=4-15corrects the problemInvestigation
The irqaffinity kernel cmdline argument is constructed using the
non_isolated_corestuned variable, which itself is defined asnon_isolated_cores=${f:cpulist_invert:${isolated_cores}}.The
cpulist_invertfunction relies on thecpulist_unpackfunction, whose documentation does not mention the "N" value.Note that this value is defined in the kernel command line documentation : https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html#cpu-lists
System
I don't know whether this is a bug report or a feature request. Do you plan to add support for the "N" value ?