(I'm not subscribed to freebsd-questions, so please CC me on replies. I'm also not sure how I ended up getting this mail in the first place; it looks like someone BCC'd my [EMAIL PROTECTED] address).
Reid, The Wikipedia article you refer to documents a very well-known topic: the SATA150-limiting jumpers on hard disks. Drive vendors have this jumper enabled (capped) by default due to incompatibilities with certain chipsets (VIA, SiS, and nVidia -- who isn't mentioned). The jumper in question is available on Western Digital and Seagate disks; I have not checked to see if Maxtor, Samsung, or Fujitsu disks offer this capability. Maxtor disks also have further incompatibilities with nVidia chipsets, specifically with regards to broken NCQ support (the disk will literally lock up/hang, causing Windows or other operating systems to blue screen or crash). A disk firmware update from Maxtor is available to fix this problem, but you have to go through Tier 1 support hell to get the patch. Additionally, the patch does not increment/change the f/w version string, so there's no way to tell if your drive already has the patch or not. (I do have the patch laying around, but I can't remember which models of Maxtor disk it affects.) Furthermore, one of the most common reports on the FreeBSD lists is the exact opposite -- users complaining that "their disks are SATA300 but only operate at SATA150" (caused by that jumper). Users are told to remove the jumper, and are reminded that the reason the jumper is enabled by default is said chipset incompatibilities. That said, your mail confuses me for one reason: Were you receiving DMA errors with the jumper REMOVED (e.g. SATA300 operation), or with the jumper ENABLED (SATA150 operation)? Your below description does not state what exactly you did with the jumper to make your drives work reliably, only "that the jumper capability on your disks was available". -- | Jeremy Chadwick jdc at parodius.com | | Parodius Networking http://www.parodius.com/ | | UNIX Systems Administrator Mountain View, CA, USA | | Making life hard for others since 1977. PGP: 4BD6C0CB | On Mon, Sep 29, 2008 at 04:19:22PM -0500, Reid Linnemann wrote: > I've seen a number of people having DMA troubles with SATA disks on > FreeBSD6 and FreeBSD7, and I'm in the same boat. A while back I posted > looking for help but none could really be found. Today I finally got to > the bottom of things (at least so far). > > Hardware incompatibility. > > According to > http://en.wikipedia.org/wiki/SATA#SATA_1.5_Gbit.2Fs_and_SATA_3_Gbit.2Fs > there is an upward compatibility problem between a number of VIA and SiS > chipsets and SATA300 disks. I happen to have one of those controllers > (SiS964) and a pair of WD1600AAJS disks, which are SATA300 disks. > > I ripped apart my machine, and sure enough I had a jumper on each disk > labelled 'OPT1', which is documented to force SATA150 operation. > > I've since cold booted, warm booted, and booted after a power > interruption with no READ_DMA timeouts on these disks. I think this > solved the problem in my case. _______________________________________________ email@example.com mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"