Return to BSD News archive
Path: sserve!newshost.anu.edu.au!harbinger.cc.monash.edu.au!newshost.marcam.com!zip.eecs.umich.edu!newsxfer.itd.umich.edu!news.itd.umich.edu!pha From: pha@umich.edu (Paul H. Anderson) Newsgroups: comp.unix.bsd.freebsd.misc Subject: Re: NCR53C815? Date: 11 Mar 1995 15:55:58 GMT Organization: University of Michigan Lines: 52 Message-ID: <3jsh6e$8d3@lastactionhero.rs.itd.umich.edu> References: <3jikpm$2b8@marton.hsr.no> <3jkjdr$hip@news.rrz.uni-koeln.de> NNTP-Posting-Host: grenade.ifs.umich.edu In article <3jkjdr$hip@news.rrz.uni-koeln.de>, Stefan Esser <se@MI.Uni-Koeln.DE> wrote: >In article <3jikpm$2b8@marton.hsr.no>, vebjorn@hsr.no (Vebjoern Forsmo) writes: >|> I've got an Intel NCR 53C815-based PCI SCSI-controller. Does anyone know >|> of a kernel that supports this controller? > >The NCR 53c810, 815 and 825 are supported in >FreeBSD-current (and ought to be in the latest >SNAP). In fact, the only difference (visible >to the driver) between the 810 and 815 is the >different PCI device ID. > >We didn't have the hardware to do WIDE SCSI >tests with the 53c825, but got success reports. > Stefan Esser Internet: <se@ZPR.Uni-Koeln.DE> I am running FreeBSD 1.5.1R with Stefan and Wolf's driver on a P-90 with a Tyan MB and Tyan NCR 53C825 controller along with 4 2GB FW barracuda drives (7200RPM). I took the driver and patched it into the kernel, it built with no problems, as I recall. I have had no problems with the software, but operator error took a bit of messing with to get straightened out. You have to use the -d0 option on newfs, because it defaults to 4 milliseconds (oops). Performance is good, but possibly less than I was hoping for. Using dd to/from the raw devices gives approximately 5MB/sec (large sequential files, 1K/8K fresh filesystem). Doing mmap of large files and touching all the pages gives about 3.0 MB/sec. Doing simultaneous drives with raw reads results in peak performance of about 8.0MB/sec for the controller (I think this was with three drives running flat out). I suspect the cost of SCSI commands begins to cost more than actually moving data. I recall that I did these tests with a number of different combinations of tags and other options. Setting the bus to synchronous really killed performance. Iozone, as I recall, gave a peak of about 2.5MB/sec. Maybe there are some drive options I need to look at changing, possibly to make synchronous SCSI work? Anyone have suggestions for how to make things likely go faster? I'm hardly complaining, this is easily the fastest desktop computer I've ever used... (*: Anyhow, now I'm trying to upgrade to 2.0 from the walnut creek CDROM, but not having any luck with my P90 (possible floppy drive problem, or device interaction problem -- specific error comes trying to mount the root partition, floppy driver reports it can't read cyl 0, track 0, sector 17 or around there...). I'll know more after this weekend. Anyhow, many thanks to Stefan and Wolfgang for a job really well done! Paul Anderson pha@umich.edu