Hi!
Ive been following a OpenBSD thread from Dec 2003 "Issues multitasking during disk IO", and no "good" answer has still been given. I experience the same problems as he did. But ill explain my problem below for you who doesnt want to read a hole new thread.
First off, i been using OpenBSD in different server environments like WWW, DB, FW, IPSEC GW and others since 2.9. Ive been very pleased so far. I should also note that im the "adminstrator-type", not a programmer, please respect that in your answers. Now after a few years experience with OpenBSD i decided to leave my precious windows workstation (since its the last windowsmachine around here) for a different client-system.
The problem:
When using disk-io intensive operations like "mv /some-big-file /disk2" i cant really do ANYTHING else. Everything just halts except the mv process.
This is NOT an IDE-problem (yes it is, but other OS obviously solved it). Im running on a P4 1.8Ghz 1GB RAM and got 3 ~100Gb disks (see dmesg below).
My simple guess is that OpenBSD sets its time frames WAY to long, for a workstation with multitasking that is. People talks a lot about preemptive processing regarding this issue, i have no clue.
Ive tried to copy this behavior on other OpenBSD systems i control, and its the same problem there, i just never had a problem with it until i wanted to use it as a workstation.
Hopefully it can be fixed with a kernel parameter or some sysctl config. Dont know what kind of stats you need, since i belive everybody got the same problem.
With best regards /Jimmy
Dmesg:
OpenBSD 3.5 (GENERIC) #34: Mon Mar 29 12:24:55 MST 2004
deraadt@i386.openbsd.org:/usr/src/sys/arch/i386/compile/GENERIC
cpu0: Intel(R) Pentium(R) 4 CPU 1.80GHz ("GenuineIntel" 686-class) 1.80 GHz
cpu0: FPU,V86,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,ACPI,MMX,FXSR,SSE,SSE 2,SS,HTT,TM
real mem = 1072771072 (1047628K)
avail mem = 989417472 (966228K)
using 4278 buffers containing 53739520 bytes (52480K) of memory
mainbus0 (root)
bios0 at mainbus0: AT/286+(00) BIOS, date 03/18/02, BIOS32 rev. 0 @ 0xffe90
apm0 at bios0: Power Management spec V1.2
apm0: AC on, battery charge unknown
pcibios0 at bios0: rev. 2.1 @ 0xf0000/0x10000
pcibios0: PCI IRQ Routing Table rev. 1.0 @ 0xfbaa0/176 (9 entries)
pcibios0: PCI Interrupt Router at 000:31:0 ("Intel 82801BA LPC" rev 0x00)
pcibios0: PCI bus #2 is the last bus
bios0: ROM list: 0xc0000/0xc800 0xcc800/0x3800
pci0 at mainbus0 bus 0: configuration mode 1 (no bios)
pchb0 at pci0 dev 0 function 0 "Intel 82850 Host" rev 0x04: rng active, 7Kb/sec
ppb0 at pci0 dev 1 function 0 "Intel 82850/82860 AGP" rev 0x04
pci1 at ppb0 bus 1
vga1 at pci1 dev 0 function 0 "Nvidia GeForce3 Ti 500" rev 0xa3
wsdisplay0 at vga1: console (80x25, vt100 emulation)
wsdisplay0: screen 1-5 added (80x25, vt100 emulation)
ppb1 at pci0 dev 30 function 0 "Intel 82801BA AGP" rev 0x04
pci2 at ppb1 bus 2
emu0 at pci2 dev 7 function 0 "Creative Labs SoundBlaster Live" rev 0x0a: irq 3
ac97: codec id 0x54524123 (TriTech Microelectronics TR28602)
audio0 at emu0
"Creative Labs SoundBlaster Live Digital Input" rev 0x0a at pci2 dev 7 function 1 not configured
fxp0 at pci2 dev 8 function 0 "Intel 82557" rev 0x05: irq 10, address 00:08:c7:f3:48:4f
inphy0 at fxp0 phy 1: i82555 10/100 media interface, rev. 0
dc0 at pci2 dev 9 function 0 "Davicom Technologies DM9102" rev 0x31: irq 11, address 00:08:a1:1d:3d:cc
amphy0 at dc0 phy 1: Am79C873 10/100 media interface, rev. 0
"Texas Instruments TSB12LV26 FireWire" rev 0x00 at pci2 dev 10 function 0 not configured
pcib0 at pci0 dev 31 function 0 "Intel 82801BA LPC" rev 0x04
pciide0 at pci0 dev 31 function 1 "Intel 82801BA IDE" rev 0x04: DMA, channel 0 wired to compatibility, channel 1 wired to compatibility
wd0 at pciide0 channel 0 drive 0: <WDC WD1000BB-75CHE0>
wd0: 16-sector PIO, LBA, 95396MB, 195371568 sectors
wd1 at pciide0 channel 0 drive 1: <IC35L120AVV207-0>
wd1: 16-sector PIO, LBA48, 117800MB, 241254720 sectors
wd0(pciide0:0:0): using PIO mode 4, Ultra-DMA mode 5
wd1(pciide0:0:1): using PIO mode 4, Ultra-DMA mode 5
wd2 at pciide0 channel 1 drive 0: <ST3120026A>
wd2: 16-sector PIO, LBA48, 114473MB, 234441648 sectors
wd2(pciide0:1:0): using PIO mode 4, Ultra-DMA mode 5
uhci0 at pci0 dev 31 function 2 "Intel 82801BA USB" rev 0x04: irq 11
usb0 at uhci0: USB revision 1.0
uhub0 at usb0
uhub0: Intel UHCI root hub, class 9/0, rev 1.00/1.00, addr 1
uhub0: 2 ports with 2 removable, self powered
"Intel 82801BA SMBus" rev 0x04 at pci0 dev 31 function 3 not configured
uhci1 at pci0 dev 31 function 4 "Intel 82801BA USB2" rev 0x04: irq 9
usb1 at uhci1: USB revision 1.0
uhub1 at usb1
uhub1: Intel UHCI root hub, class 9/0, rev 1.00/1.00, addr 1
uhub1: 2 ports with 2 removable, self powered
isa0 at pcib0
isadma0 at isa0
pckbc0 at isa0 port 0x60/5
pckbd0 at pckbc0 (kbd slot)
pckbc0: using irq 1 for kbd slot
wskbd0 at pckbd0: console keyboard, using wsdisplay0
pms0 at pckbc0 (aux slot)
pckbc0: using irq 12 for aux slot
wsmouse0 at pms0 mux 0
pcppi0 at isa0 port 0x61
midi0 at pcppi0: <PC speaker>
sysbeep0 at pcppi0
lpt0 at isa0 port 0x378/4 irq 7
npx0 at isa0 port 0xf0/16: using exception 16
pccom0 at isa0 port 0x3f8/8 irq 4: ns16550a, 16 byte fifo
fdc0 at isa0 port 0x3f0/6 irq 6 drq 2
fd0 at fdc0 drive 0: 1.44MB 80 cyl, 2 head, 18 sec
biomask ca40 netmask ce40 ttymask dec2
pctr: user-level cycle counter enabled
dkcsum: wd0 matched BIOS disk 80
dkcsum: wd1 matched BIOS disk 81
dkcsum: wd2 matched BIOS disk 82
root on wd0a
rootdev=0x0 rrootdev=0x300 rawdev=0x302
OpenBSD bad Multitasking?