Mike,
On Tue, Jun 17, 2014 at 10:30:23AM -0700, Mike Larkin wrote:
> On Tue, Jun 17, 2014 at 05:10:51AM -0400, Brad Smith wrote:
> > Because ACPI is in use which takes higher precedence over MP BIOS. You
> > have to disable acpimadt.
> >
>
> Randomly disabling parts of the kernel is likely to cause other problems.
>
I agree, but disabling mpbios and acpimadt makes a huge difference for me
on qemu-kvm-1.5.3-60.el7.x86_64:
#### OpenBSD i386/virtio (bsd.sp disable mpbios and acpimadt) ####
# time dd if=/dev/zero of=/tmp/TEST bs=4096 count=1024x1024
1048576+0 records in
1048576+0 records out
4294967296 bytes transferred in 18.524 secs (231854084 bytes/sec)
0m18.52s real 0m0.24s user 0m14.48s system
It takes now 18 seconds to run above dd(1), when previously it took 60
mintues. Thanks Christiano and Brad for the tips.
Do you guys think it's worth opening bug report with RedHat to get them
look into this, or is the problem more on OpenBSD side? Ideally I would
like to run unmodified OpenBSD kernel on my VMs.
$ diff -I'^iic0' dmesg.txt disable-mpbios-and-acpimadt.txt
--- dmesg.txt Sat Jun 14 15:49:02 2014
+++ disable-mpbios-and-acpimadt.txt Tue Jun 17 13:30:46 2014
@@ -4,6 +4,13 @@
cpu0:
FPU,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,MMX,FXSR,SSE,SSE2,NXE,LONG,SSE3,CX16,LAHF,ABM,SSE4A,PERF
real mem = 536367104 (511MB)
avail mem = 515158016 (491MB)
+User Kernel Config
+UKC> disable mpbios
+368 mpbios0 disabled
+UKC> disable acpimadt
+501 acpimadt0 disabled
+UKC> quit
+Continuing...
mpath0 at root
scsibus0 at mpath0: 256 targets
mainbus0 at root
@@ -15,22 +22,20 @@
acpi0: tables DSDT FACP SSDT APIC RSDT
acpi0: wakeup devices
acpitimer0 at acpi0: 3579545 Hz, 24 bits
-acpimadt0 at acpi0 addr 0xfee00000: PC-AT compat
-cpu0 at mainbus0: apid 0 (boot processor)
-mtrr: Pentium Pro MTRR support, 8 var ranges, 88 fixed ranges
-cpu0: apic clock running at 999MHz
-ioapic0 at mainbus0: apid 0 pa 0xfec00000, version 11, 24 pins
acpiprt0 at acpi0: bus 0 (PCI0)
acpicpu0 at acpi0
+mpbios at bios0 function 0x0 not configured
bios0: ROM list: 0xc0000/0x1000! 0xc1000/0xa00 0xc2000/0x2400 0xed800/0x2800!
+cpu0 at mainbus0: (uniprocessor)
+mtrr: Pentium Pro MTRR support, 8 var ranges, 88 fixed ranges
pci0 at mainbus0 bus 0: configuration mode 1 (bios)
pchb0 at pci0 dev 0 function 0 "Intel 82441FX" rev 0x02
pcib0 at pci0 dev 1 function 0 "Intel 82371SB ISA" rev 0x00
pciide0 at pci0 dev 1 function 1 "Intel 82371SB IDE" rev 0x00: DMA, channel 0
wired to compatibility, channel 1 wired to compatibility
pciide0: channel 0 disabled (no drives)
pciide0: channel 1 disabled (no drives)
-uhci0 at pci0 dev 1 function 2 "Intel 82371SB USB" rev 0x01: apic 0 int 11
-piixpm0 at pci0 dev 1 function 3 "Intel 82371AB Power" rev 0x03: apic 0 int 9
+uhci0 at pci0 dev 1 function 2 "Intel 82371SB USB" rev 0x01: irq 11
+piixpm0 at pci0 dev 1 function 3 "Intel 82371AB Power" rev 0x03: irq 9
iic0 at piixpm0
iic0: addr 0x1c 0f=00 words 00=d4d0 01=d4d0 02=d4d0 03=d4d0 04=d4d0 05=d4d0
06=d4d0 07=d4d0
iic0: addr 0x1d 0f=00 words 00=d4d0 01=d4d0 02=d4d0 03=d4d0 04=d4d0 05=d4d0
06=d4d0 07=d4d0
@@ -39,13 +44,13 @@
iic0: addr 0x4e 00=00 01=00 02=00 03=00 04=00 05=00 06=00 07=00 08=00 3e=d1
48=d1 4a=d1 4e=d1 fc=d1 fe=d1 words 00=9d87 01=9d87 02=9d87 03=9d87 04=9d87
05=9d87 06=9d87 07=9d87
virtio0 at pci0 dev 3 function 0 "Qumranet Virtio Network" rev 0x00: Virtio
Network Device
vio0 at virtio0: address 52:54:00:12:34:70
-virtio0: apic 0 int 11
+virtio0: irq 11
virtio1 at pci0 dev 4 function 0 "Qumranet Virtio Storage" rev 0x00: Virtio
Block Device
vioblk0 at virtio1
scsibus1 at vioblk0: 2 targets
sd0 at scsibus1 targ 0 lun 0: <VirtIO, Block Device, > SCSI3 0/direct fixed
sd0: 102400MB, 512 bytes/sector, 209715200 sectors
-virtio1: apic 0 int 11
+virtio1: irq 11
isa0 at pcib0
isadma0 at isa0
com0 at isa0 port 0x3f8/8 irq 4: ns16550a, 16 byte fifo
--
best regards
q#
