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

I found one link to the thread here. If you have a better link, please post it.

The original poster in that thread said If a kernel tweak could fix this, I have to believe that tweak would have surfaced by now. But maybe someone will have an idea for you. In the meantime, could you comment on what's wrong with the obvious solution of simply switching to linux or freebsd?

Well, ive growned use to the OpenBSD environment when setting up servers. Unfortionaly ive never experienced the bad workstation parts...

Otherwise, i like both FreeBSD and Linux to.