tech-kern archive

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Old Index]

Re: Interrupt time inflation on Xen



Thor Lancelot Simon <tls%panix.com@localhost> writes:

> The same test's easy to reproduce with any Xen dom0, since all you have
> to do is dd from the raw disk into /dev/null.  Do you see >40% interrupt
> time and all your idle CPU go away?  That's the issue.

14% sys, mostly idle 1000 interrupts on what looks like the disk ioapic
pin, and 1000 xfer/s, total interrupts 1000-200.
netbsd-6, i386 XEN3PAE_DOM0

Also ok on netbsd-5 XEN3_DOM0 amd64 (disk at disk speed, low sys, right
number of disk interrupts, mostly idle).

Both systems have normal mobo disk contr1ollers.  The second is:

acpi0: X/RSDT: OemId <INTEL ,DG33FB  ,000001fb>, AslId <    ,01000013>
piixide0 at pci0 dev 31 function 2
piixide0: Intel 82801I Serial ATA Controller (ICH9) (rev. 0x02)
piixide0: bus-master DMA support present
piixide0: primary channel configured to native-PCI mode
piixide0: using ioapic0 pin 21, event channel 5 for native-PCI interrupt
atabus2 at piixide0 channel 0
piixide0: secondary channel configured to native-PCI mode
atabus3 at piixide0 channel 1
piixide1 at pci0 dev 31 function 5
piixide1: Intel 82801I Serial ATA Controller (ICH9) (rev. 0x02)
piixide1: bus-master DMA support present
piixide1: primary channel wired to native-PCI mode
piixide1: using ioapic0 pin 21, event channel 5 for native-PCI interrupt
atabus4 at piixide1 channel 0
piixide1: secondary channel wired to native-PCI mode
atabus5 at piixide1 channel 1
wd0 at atabus2 drive 0: <ST3750640NS>
wd0: drive supports 16-sector PIO transfers, LBA48 addressing
wd0: 698 GB, 1453521 cyl, 16 head, 63 sec, 512 bytes/sect x 1465149168 sectors
wd0: 32-bit data port
wd0: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 6 (Ultra/133)
wd0(piixide0:0:0): using PIO mode 4, Ultra-DMA mode 6 (Ultra/133) (using DMA)

I wonder if this is a netbsd-7 vs netbsd-6 thing.  Or only triggered by
some interrupt mappings.

Attachment: signature.asc
Description: PGP signature



Home | Main Index | Thread Index | Old Index