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Bug 2014065

Summary: IRQBALANCE_BANNED_CPUS: improve documentation and logging
Product: Red Hat Enterprise Linux 8 Reporter: Florencia Fotorello <ffotorel>
Component: irqbalanceAssignee: ltao
Status: CLOSED ERRATA QA Contact: Jiri Dluhos <jdluhos>
Severity: low Docs Contact:
Priority: low    
Version: 8.5CC: jeder, jshortt, ltao, myamazak, ruyang, rvr
Target Milestone: rcKeywords: Triaged
Target Release: ---Flags: pm-rhel: mirror+
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: irqbalance-1.9.0-2.el8 Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2022-11-08 10:54:58 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Comment 9 Jiri Dluhos 2022-07-28 00:44:16 UTC
Confirming that the strings in the debug log, as per comment#6, are at their places.
Setting Verified:Tested (please note comment#8 though for a small typo found).

Comment 13 Jiri Dluhos 2022-08-02 22:25:06 UTC
Confirming the irqbalance-1.9.0-3.el8.rpm contains the requested documentation changes. Also, the binary contains the requested strings, and seems to print them out properly.

# rpm -qi irqbalance | head -n 4
Name        : irqbalance
Epoch       : 2
Version     : 1.9.0
Release     : 3.el8

# man irqbalance | grep BANNED_CPUS --context 2
              Same as --debug.

       IRQBALANCE_BANNED_CPUS
              Provides a mask of CPUs which irqbalance should ignore and never assign interrupts to.  If not specified, irqbalance use mask of isolated and adaptive-ticks CPUs on the system as the default
              value. The "isolcpus=" boot parameter specifies the isolated CPUs. The "nohz_full=" boot parameter specifies the adaptive-ticks CPUs. By default, no CPU will be an isolated or adaptive-ticks
              CPU.   This  is  a  hexmask  without  the  leading  ’0x’.  On  systems  with  large  numbers  of processors, each group of eight hex digits is separated by a comma ’,’. i.e.  ‘export IRQBAL‐
              ANCE_BANNED_CPUS=fc0‘ would prevent irqbalance from assigning irqs to the 7th-12th cpus (cpu6-cpu11)  or  ‘export  IRQBALANCE_BANNED_CPUS=ff000000,00000001‘  would  prevent  irqbalance  from
              assigning  irqs  to  the  1st (cpu0) and 57th-64th cpus (cpu56-cpu63).  Notes: This environment variable will be discarded, please use IRQBALANCE_BANNED_CPULIST instead. Before deleting this
              environment variable, Introduce a deprecation period first for the consider of compatibility.

# strings /usr/sbin/irqbalance | grep -i 'Prevent IRQ'
Prevent irq assignment to these isolated CPUs: %s
Prevent irq assignment to these adaptive-ticks CPUs: %s

# strings /usr/sbin/irqbalance | grep -i 'There is no suitable'
There is no suitable CPU in node:%d.

# strings /usr/sbin/irqbalance | grep -i 'Irqbalance dispatch'
Irqbalance dispatch irq:%d to other node.

Comment 15 errata-xmlrpc 2022-11-08 10:54:58 UTC
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (irqbalance bug fix and enhancement update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2022:7787