After upgrading to current (snapshot from Nov. 25) OpenBSD seems to be choking on large (>2GB) files (tested with GENERIC.MP and GENERIC):
$ pwd /home/user $ mount ... /dev/wd0k on /home type ffs (local, nodev, nosuid, softdep) ... $ dd if=/dev/zero of=large1 bs=1024 count=2500000 2500000+0 records in 2500000+0 records out 2560000000 bytes transferred in 80.225 secs (31910238 bytes/sec) $ cat large1 >large2 cat: large1: Invalid argument $ ls -lh large* -rw-r--r-- 1 user user 2.4G Nov 27 11:38 large1 -rw-r--r-- 1 user user 2.0G Nov 27 11:42 large2 $ rm large2 $ cp large1 large2 cp: large1: Invalid argument $ ls -lh large* -rw-r--r-- 1 user user 2.4G Nov 27 11:38 large1 -rw-r--r-- 1 user user 0B Nov 27 11:42 large2 OpenBSD 5.0-current (GENERIC.MP) #130: Fri Nov 25 00:28:08 MST 2011 dera...@i386.openbsd.org:/usr/src/sys/arch/i386/compile/GENERIC.MP cpu0: Intel(R) Atom(TM) CPU N270 @ 1.60GHz ("GenuineIntel" 686-class) 1.60 GHz cpu0: FPU,V86,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,SBF,NXE,SSE3,MWAIT,DS-CPL,EST,TM2,SSSE3,xTPR,PDCM,MOVBE,LAHF real mem = 1061416960 (1012MB) avail mem = 1033936896 (986MB) mainbus0 at root bios0 at mainbus0: AT/286+ BIOS, date 03/06/09, SMBIOS rev. 2.6 @ 0xe91f0 (42 entries) bios0: vendor Intel Corp. version "JT94510H.86A.0025.2009.0306.1639" date 03/06/2009 bios0: Intel Corporation D945GSEJT acpi0 at bios0: rev 2 acpi0: sleep states S0 S1 S3 S4 S5 acpi0: tables DSDT FACP APIC MCFG SSDT SSDT SSDT acpi0: wakeup devices P0P2(S4) PEGP(S4) USB0(S3) USB1(S3) USB2(S3) USB3(S3) EHCI(S3) MC97(S4) P0P1(S4) PS2K(S3) PS2M(S3) UAR1(S3) UAR2(S3) P0P4(S4) P0P5(S4) P0P6(S4) PWRB(S3) acpitimer0 at acpi0: 3579545 Hz, 24 bits acpimadt0 at acpi0 addr 0xfee00000: PC-AT compat cpu0 at mainbus0: apid 0 (boot processor) cpu0: apic clock running at 133MHz cpu1 at mainbus0: apid 1 (application processor) cpu1: Intel(R) Atom(TM) CPU N270 @ 1.60GHz ("GenuineIntel" 686-class) 1.60 GHz cpu1: FPU,V86,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,SBF,NXE,SSE3,MWAIT,DS-CPL,EST,TM2,SSSE3,xTPR,PDCM,MOVBE,LAHF ioapic0 at mainbus0: apid 2 pa 0xfec00000, version 20, 24 pins acpimcfg0 at acpi0 addr 0xe0000000, bus 0-255 acpiprt0 at acpi0: bus 0 (PCI0) acpiprt1 at acpi0: bus -1 (P0P2) acpiprt2 at acpi0: bus 5 (P0P1) acpiprt3 at acpi0: bus 1 (P0P4) acpiprt4 at acpi0: bus 2 (P0P5) acpicpu0 at acpi0: C3, C2, C1, PSS acpicpu1 at acpi0: C3, C2, C1, PSS acpibtn0 at acpi0: PWRB acpivideo0 at acpi0: IGD_ bios0: ROM list: 0xc0000/0xec00! 0xcf000/0x1000 cpu0: Enhanced SpeedStep 1597 MHz: speeds: 1600, 1333, 1067, 800 MHz pci0 at mainbus0 bus 0: configuration mode 1 (bios) pchb0 at pci0 dev 0 function 0 "Intel 82945GME Host" rev 0x03 vga1 at pci0 dev 2 function 0 "Intel 82945GME Video" rev 0x03 wsdisplay0 at vga1 mux 1: console (80x25, vt100 emulation) wsdisplay0: screen 1-5 added (80x25, vt100 emulation) intagp0 at vga1 agp0 at intagp0: aperture at 0xd0000000, size 0x10000000 inteldrm0 at vga1: apic 2 int 16 drm0 at inteldrm0 "Intel 82945GM Video" rev 0x03 at pci0 dev 2 function 1 not configured azalia0 at pci0 dev 27 function 0 "Intel 82801GB HD Audio" rev 0x02: msi azalia0: codecs: Realtek ALC662 audio0 at azalia0 ppb0 at pci0 dev 28 function 0 "Intel 82801GB PCIE" rev 0x02 pci1 at ppb0 bus 1 re0 at pci1 dev 0 function 0 "Realtek 8168" rev 0x03: RTL8168D/8111D (0x2800), apic 2 int 16, address 00:27:0e:01:8f:99 rgephy0 at re0 phy 7: RTL8169S/8110S PHY, rev. 2 ppb1 at pci0 dev 28 function 1 "Intel 82801GB PCIE" rev 0x02 pci2 at ppb1 bus 2 ppb2 at pci0 dev 28 function 2 "Intel 82801GB PCIE" rev 0x02 pci3 at ppb2 bus 3 ppb3 at pci0 dev 28 function 3 "Intel 82801GB PCIE" rev 0x02 pci4 at ppb3 bus 4 uhci0 at pci0 dev 29 function 0 "Intel 82801GB USB" rev 0x02: apic 2 int 23 uhci1 at pci0 dev 29 function 1 "Intel 82801GB USB" rev 0x02: apic 2 int 19 uhci2 at pci0 dev 29 function 2 "Intel 82801GB USB" rev 0x02: apic 2 int 18 uhci3 at pci0 dev 29 function 3 "Intel 82801GB USB" rev 0x02: apic 2 int 16 ehci0 at pci0 dev 29 function 7 "Intel 82801GB USB" rev 0x02: apic 2 int 23 ehci0: timed out waiting for BIOS usb0 at ehci0: USB revision 2.0 uhub0 at usb0 "Intel EHCI root hub" rev 2.00/1.00 addr 1 ppb4 at pci0 dev 30 function 0 "Intel 82801BAM Hub-to-PCI" rev 0xe2 pci5 at ppb4 bus 5 ichpcib0 at pci0 dev 31 function 0 "Intel 82801GBM LPC" rev 0x02: PM disabled pciide0 at pci0 dev 31 function 1 "Intel 82801GB IDE" rev 0x02: DMA, channel 0 configured to compatibility, channel 1 configured to compatibility pciide0: channel 0 disabled (no drives) pciide0: channel 1 disabled (no drives) pciide1 at pci0 dev 31 function 2 "Intel 82801GBM SATA" rev 0x02: DMA, channel 0 configured to native-PCI, channel 1 configured to native-PCI pciide1: using apic 2 int 19 for native-PCI interrupt wd0 at pciide1 channel 0 drive 0: <WDC WD1600BEVT-00ZCT0> wd0: 16-sector PIO, LBA48, 152627MB, 312581808 sectors wd0(pciide1:0:0): using PIO mode 4, Ultra-DMA mode 6 ichiic0 at pci0 dev 31 function 3 "Intel 82801GB SMBus" rev 0x02: apic 2 int 19 iic0 at ichiic0 spdmem0 at iic0 addr 0x50: 1GB DDR2 SDRAM non-parity PC2-6400CL5 SO-DIMM usb1 at uhci0: USB revision 1.0 uhub1 at usb1 "Intel UHCI root hub" rev 1.00/1.00 addr 1 usb2 at uhci1: USB revision 1.0 uhub2 at usb2 "Intel UHCI root hub" rev 1.00/1.00 addr 1 usb3 at uhci2: USB revision 1.0 uhub3 at usb3 "Intel UHCI root hub" rev 1.00/1.00 addr 1 usb4 at uhci3: USB revision 1.0 uhub4 at usb4 "Intel UHCI root hub" rev 1.00/1.00 addr 1 isa0 at ichpcib0 isadma0 at isa0 com0 at isa0 port 0x3f8/8 irq 4: ns16550a, 16 byte fifo com1 at isa0 port 0x2f8/8 irq 3: ns16550a, 16 byte fifo 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 pcppi0 at isa0 port 0x61 spkr0 at pcppi0 lpt0 at isa0 port 0x378/4 irq 7 wbsio0 at isa0 port 0x2e/2: W83627DHG-P rev 0x73 lm1 at wbsio0 port 0xa00/8: W83627DHG npx0 at isa0 port 0xf0/16: reported by CPUID; using exception 16 mtrr: Pentium Pro MTRR support uhub5 at uhub0 port 7 "Genesys Logic USB2.0 Hub" rev 2.00/7.02 addr 2 uhidev0 at uhub5 port 4 configuration 1 interface 0 "CHESEN PS2 to USB Converter" rev 1.10/0.10 addr 3 uhidev0: iclass 3/1 ukbd0 at uhidev0: 8 modifier keys, 6 key codes wskbd1 at ukbd0 mux 1 wskbd1: connecting to wsdisplay0 uhidev1 at uhub5 port 4 configuration 1 interface 1 "CHESEN PS2 to USB Converter" rev 1.10/0.10 addr 3 uhidev1: iclass 3/1, 3 report ids ums0 at uhidev1 reportid 1: 5 buttons, Z dir wsmouse0 at ums0 mux 0 uhid0 at uhidev1 reportid 2: input=1, output=0, feature=0 uhid1 at uhidev1 reportid 3: input=3, output=0, feature=0 vscsi0 at root scsibus0 at vscsi0: 256 targets softraid0 at root scsibus1 at softraid0: 256 targets root on wd0a (62b8c59112bdb195.a) swap on wd0b dump on wd0b