Bug#577788: dom0 kernels should suggest irqbalance
Control: reassign -1 src:linux COntrol: retitle -1 SMP kernels should suggest irqbalance On Thu, 2014-09-04 at 00:14 +0100, Ben Hutchings wrote: On Sun, 2014-08-31 at 03:10 +0100, Ian Campbell wrote: (copying debian-kernel for reasons which will hopefully become obvious) On Mon, 8 Jul 2013 18:10:58 +0200 =?UTF-8?Q?Moritz_M=C3=BChlenhoff?= j...@inutil.org wrote: In current Debian kernel there's no special Xen dom0 kernel image and depending on irqbalance in the kernel package would be overkill. Would it? I thought irqbalance is actually required even for native with modern kernels, since the kernel doesn't do any balancing by itself (any more, it did use to). I don't know that it's generally required, but it can be useful if there is a lot of work done in interrupt or softirq context (and have multiple processors). Looking on my laptop for instance I see that all interrupts are going to CPU0 out of the 4 processes. On the other hand my workstation does seem to have balanced IRQs despite having no irqbalanced running, so I don't know. I reckon the kernel probably should recommend irqbalance these days, but in any case there is no reason for Xen to do something different (since IRQ balancing should work as on native). At least kernels that support SMP could recommend it. That sounds like a good idea to me. Presumably irqbalanced is mostly harmless for UP kernels, but I think we can avoid that recommends unless the auto-generation of debian/control gets in the way too much. Ian. -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Bug#577788: dom0 kernels should suggest irqbalance
On Sun, 2014-08-31 at 03:10 +0100, Ian Campbell wrote: (copying debian-kernel for reasons which will hopefully become obvious) On Mon, 8 Jul 2013 18:10:58 +0200 =?UTF-8?Q?Moritz_M=C3=BChlenhoff?= j...@inutil.org wrote: In current Debian kernel there's no special Xen dom0 kernel image and depending on irqbalance in the kernel package would be overkill. Would it? I thought irqbalance is actually required even for native with modern kernels, since the kernel doesn't do any balancing by itself (any more, it did use to). I don't know that it's generally required, but it can be useful if there is a lot of work done in interrupt or softirq context (and have multiple processors). Looking on my laptop for instance I see that all interrupts are going to CPU0 out of the 4 processes. On the other hand my workstation does seem to have balanced IRQs despite having no irqbalanced running, so I don't know. I reckon the kernel probably should recommend irqbalance these days, but in any case there is no reason for Xen to do something different (since IRQ balancing should work as on native). At least kernels that support SMP could recommend it. Ben. -- Ben Hutchings Experience is directly proportional to the value of equipment destroyed. - Carolyn Scheppner signature.asc Description: This is a digitally signed message part
Bug#577788: dom0 kernels should suggest irqbalance
(copying debian-kernel for reasons which will hopefully become obvious) On Mon, 8 Jul 2013 18:10:58 +0200 =?UTF-8?Q?Moritz_M=C3=BChlenhoff?= j...@inutil.org wrote: In current Debian kernel there's no special Xen dom0 kernel image and depending on irqbalance in the kernel package would be overkill. Would it? I thought irqbalance is actually required even for native with modern kernels, since the kernel doesn't do any balancing by itself (any more, it did use to). Looking on my laptop for instance I see that all interrupts are going to CPU0 out of the 4 processes. On the other hand my workstation does seem to have balanced IRQs despite having no irqbalanced running, so I don't know. I reckon the kernel probably should recommend irqbalance these days, but in any case there is no reason for Xen to do something different (since IRQ balancing should work as on native). Ian. -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Bug#577788: dom0 kernels should suggest irqbalance
reassign 577788 src:xen thanks On Wed, Apr 14, 2010 at 05:00:03PM +0200, Adi Kriegisch wrote: Package: xen-linux-system-2.6.32-4-xen-686 Version: 2.6.32-11 Severity: minor I recently[1] noticed that a kernel booted as Dom0 does attach all interrupts to CPU0 which may lead to performance issues. Suggesting/recomending 'irqbalance' and probably mention the issue in README.Debian should suffice, I guess. RedHat Enterprise Server[2] seems to have this package installed by default; I could not find any details about Novell/SuSE... In current Debian kernel there's no special Xen dom0 kernel image and depending on irqbalance in the kernel package would be overkill. If irqbalance it generally useful for dom0 operation, it should rather be recommended by the Xen hypervisor packages. Reassigning. Cheers, Moritz -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
Bug#577788: dom0 kernels should suggest irqbalance
Package: xen-linux-system-2.6.32-4-xen-686 Version: 2.6.32-11 Severity: minor I recently[1] noticed that a kernel booted as Dom0 does attach all interrupts to CPU0 which may lead to performance issues. Suggesting/recomending 'irqbalance' and probably mention the issue in README.Debian should suffice, I guess. RedHat Enterprise Server[2] seems to have this package installed by default; I could not find any details about Novell/SuSE... -- Adi [1] http://lists.xensource.com/archives/html/xen-users/2010-04/msg00577.html [2] https://www.redhat.com/security/data/metrics/cpelist-rhel5server-default-install.txt -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org
