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Bug 470204
| Summary: | add s390 and s390x into ExclusiveArch | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Dan Horák <dan> |
| Component: | irqbalance | Assignee: | Neil Horman <nhorman> |
| Status: | CLOSED NOTABUG | QA Contact: | Fedora Extras Quality Assurance <extras-qa> |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 9 | CC: | dennis, gmuelas, nhorman |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | s390x | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2008-11-06 19:35:42 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
| Bug Depends On: | |||
| Bug Blocks: | 467765 | ||
|
Description
Dan Horák
2008-11-06 09:19:51 UTC
I believe that it compiles and even runs without error on s390 (given that its only interface to the kernel is via /proc). That being said however, I can't find any reason why its usefull on those arches. While one can steer interrupts to various cpus in a guest account (either via irqbalance, or manually via /proc/irq/<irq #>/smp_affinity), theres no guarantee that those interrupts will actually be steered to different physical cpus. Since you're always running on a hypervisor on these arches, theres always going to be a disconnect between what irqblance tries to do and what acutally happens on the metal. If you can come up with some evidence that irqbalance produces a benefit on these systems consistently and predictably, then I'll happily consider it, but just the fact that its runs without falling over isn't reason enough to enable it. From what I understood from one of our s390[x] kernel developers, he agrees with Neil: the interrupts in s390 are floating interrupts, that is, is not possible/there is no intention to choose the CPU, so s390x won't benefit form irqbalance. |