Well, now I'm plenty confused. I wasn't aware that IDE DMA didn't work, so this subject line caught me a bit by suprise. Maybe I just have "supported" hardware everywhere, or maybe I'm missing something and I don't even know it. Or maybe I'm just posting this for comparison purposes.
I know that this 2.5-year-old machine has an Asus motherboard of some sort: FreeBSD 4.0-CURRENT #1: Sun Jan 24 02:49:52 EST 1999 r...@lion-around.at.yiff.net:/usr/local/usr-src/sys/compile/LION-AROUND Timecounter "i8254" frequency 1193182 Hz CPU: Pentium/P54C (166.19-MHz 586-class CPU) Origin = "GenuineIntel" Id = 0x52c Stepping=12 Features=0x1bf<FPU,VME,DE,PSE,TSC,MSR,MCE,CX8> real memory = 100663296 (98304K bytes) config> quit avail memory = 94875648 (92652K bytes) Preloaded elf kernel "kernel" at 0xf02d9000. Probing for devices on PCI bus 0: chip0: <Intel 82439> rev 0x03 on pci0.0.0 chip1: <Intel 82371SB PCI to ISA bridge> rev 0x01 on pci0.7.0 ide_pci0: <Intel PIIX3 Bus-master IDE controller> rev 0x00 on pci0.7.1 [...] wdc0 at 0x1f0-0x1f7 irq 14 flags 0xa0ffa0ff on isa wdc0: unit 0 (wd0): <WDC AC32500H>, DMA, 32-bit, multi-block-16 wd0: 2441MB (4999680 sectors), 4960 cyls, 16 heads, 63 S/T, 512 B/S wdc0: unit 1 (atapi): <CD-ROM CDU311/3.0i>, removable, accel, dma, iordis acd0: drive speed 1378KB/sec, 128KB cache [...] wdc1 at 0x170-0x177 irq 15 flags 0xa0ffa0ff on isa wdc1: unit 0 (wd2): <Maxtor 91008D7>, DMA, 32-bit, multi-block-16 wd2: 9617MB (19696320 sectors), 19540 cyls, 16 heads, 63 S/T, 512 B/S On the old wd0 that I got with the machine: $ time dd if=/dev/zero of=test2 bs=32k count=1024 1024+0 records in 1024+0 records out 33554432 bytes transferred in 5.177823 secs (6480413 bytes/sec) dd if=/dev/zero of=test2 bs=32k count=1024 0.03s user 2.08s system 28% cpu 7.458 total $ time dd if=/dev/rwd0 of=/dev/null bs=32k count=1024 1024+0 records in 1024+0 records out 33554432 bytes transferred in 4.064697 secs (8255088 bytes/sec) dd if=/dev/rwd0 of=/dev/null bs=32k count=1024 0.00s user 0.14s system 3% cpu 4.070 total And on the brand spanking new Maxtor UltraDMA happy happy: $ time dd if=/dev/zero of=test2 bs=32k count=1024 1024+0 records in 1024+0 records out 33554432 bytes transferred in 3.073696 secs (10916640 bytes/sec) dd if=/dev/zero of=test2 bs=32k count=1024 0.01s user 2.26s system 72% cpu 3.124 total $ time dd if=/dev/rwd2 of=/dev/null bs=32k count=1024 1024+0 records in 1024+0 records out 33554432 bytes transferred in 2.521986 secs (13304765 bytes/sec) dd if=/dev/rwd2 of=/dev/null bs=32k count=1024 0.00s user 0.13s system 5% cpu 2.528 total Just out of curiosity, I compared with a machine with what was at the time an expensive SCSI controller. Same CPU as mine. FreeBSD 2.2.7-STABLE #0: Sat Aug 8 22:38:59 EDT 1998 [...] ahc0 <Adaptec 3940 Ultra SCSI host adapter> rev 0 int a irq 9 on pci1:4:0 ahc0: aic7880 Wide Channel A, SCSI Id=7, 16 SCBs (ahc0:0:0): "SEAGATE ST34371W 0484" type 0 fixed SCSI 2 sd0(ahc0:0:0): Direct-Access 4148MB (8496884 512 byte sectors) $ time dd if=/dev/zero of=test2 bs=32k count=1024 1024+0 records in 1024+0 records out 33554432 bytes transferred in 3.393906 secs (9886671 bytes/sec) dd if=/dev/zero of=test2 bs=32k count=1024 0.04s user 1.33s system 40% cpu 3.411 total $ time dd if=/dev/rsd0 of=/dev/null bs=32k count=1024 1024+0 records in 1024+0 records out 33554432 bytes transferred in 3.525452 secs (9517767 bytes/sec) dd if=/dev/rsd0 of=/dev/null bs=32k count=1024 0.03s user 0.12s system 2% cpu 5.330 total The bleeding edge and I have a pretty good relationship. I haven't been bitten by softupdates, IDE DMA, or the new VM (well, I did have that panic, but the fix had already become available). Of course, I'm now running afoul of 4.0-related libtool breakage in the ports collection, but it's not exactly a mystery to fix. -- Christopher Masto Director of Operations NetMonger Communications ch...@netmonger.net i...@netmonger.net http://www.netmonger.net "Good tools allow users to do stupid things." -- Clay Shirky To Unsubscribe: send mail to majord...@freebsd.org with "unsubscribe freebsd-current" in the body of the message