[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH 1/2] KVM: fix i8259 interrupt high to low transi
From: |
Maciej W. Rozycki |
Subject: |
Re: [Qemu-devel] [PATCH 1/2] KVM: fix i8259 interrupt high to low transition logic |
Date: |
Thu, 13 Sep 2012 14:41:30 +0100 (BST) |
User-agent: |
Alpine 2.00 (LFD 1167 2008-08-23) |
On Wed, 12 Sep 2012, Matthew Ogilvie wrote:
> Also, how big of a concern is a very rare gained or lost IRQ0
> actually? Under normal conditions, I would expect this to at most
> cause a one time clock drift in the guest OS of a fraction of
> a second. If that only happens when rebooting or migrating the
> guest...
It depends on how you define "very rare". Once per month or probably
even per day is probably acceptable although you'll see a disruption in
the system clock. This is still likely unwanted if the system is used as
a clock reference and not just wants to keep its clock right for own
purposes. Anything more frequent and NTP does care very much; an accurate
system clock is important in many uses, starting from basic ones such as
where timestamps of files exported over NFS are concerned.
Speaking of real hw -- I don't know whether that really matters for
emulated systems. Thanks for looking into the 8254 PIT in details.
Maciej
- Re: [Qemu-devel] [PATCH 1/2] KVM: fix i8259 interrupt high to low transition logic, (continued)
- Re: [Qemu-devel] [PATCH 1/2] KVM: fix i8259 interrupt high to low transition logic, Maciej W. Rozycki, 2012/09/10
- Re: [Qemu-devel] [PATCH 1/2] KVM: fix i8259 interrupt high to low transition logic, Avi Kivity, 2012/09/12
- Re: [Qemu-devel] [PATCH 1/2] KVM: fix i8259 interrupt high to low transition logic, Jan Kiszka, 2012/09/12
- Re: [Qemu-devel] [PATCH 1/2] KVM: fix i8259 interrupt high to low transition logic, Avi Kivity, 2012/09/12
- Re: [Qemu-devel] [PATCH 1/2] KVM: fix i8259 interrupt high to low transition logic, Jan Kiszka, 2012/09/12
- Re: [Qemu-devel] [PATCH 1/2] KVM: fix i8259 interrupt high to low transition logic, Avi Kivity, 2012/09/12
- Re: [Qemu-devel] [PATCH 1/2] KVM: fix i8259 interrupt high to low transition logic, Matthew Ogilvie, 2012/09/13
- Re: [Qemu-devel] [PATCH 1/2] KVM: fix i8259 interrupt high to low transition logic,
Maciej W. Rozycki <=
- Re: [Qemu-devel] [PATCH 1/2] KVM: fix i8259 interrupt high to low transition logic, Jan Kiszka, 2012/09/13
- Re: [Qemu-devel] [PATCH 1/2] KVM: fix i8259 interrupt high to low transition logic, Jan Kiszka, 2012/09/13
- Re: [Qemu-devel] [PATCH 1/2] KVM: fix i8259 interrupt high to low transition logic, Maciej W. Rozycki, 2012/09/13