neese@adaptx1.UUCP (03/19/91)
>STUFF DELETED< > now a question for folks out there using a similar configuration. > when i bring down the systems (via a haltsys or reboot), i must > press the reset button to affect a hard reset before the computer > will recognize the adaptec scsi controller -- do i have my system > set up wrong or is there no way to reboot xenix without a hard > reset (ie reset button or cycle the power) ??? This is due to the motherboard not asserting the AT bus reset line on a soft reset. Some motherboards do not do this and so the 154x will not know when it can do it's thing for power up. We rely on the reset line to tell use to start all over again. Roy Neese Adaptec Senior SCSI Applications Engineer UUCP @ neese@adaptex uunet!cs.utexas.edu!utacfd!merch!adaptex!neese
neese@adaptx1.UUCP (03/19/91)
> I am having a problem with SCO Xenix 2.3.2GT and very low disk >transfer rates. Here is my configuration: >33 MHz 386 w/387 >8 Meg ram >128K cache >Adaptec 1542B DMA=5 irq=11 i/o base=330, bios enabled, 5 Meg DMA transfer rate >Wren V 330 Meg SCSI drive >Archive 2150S tape drive >Digiboard Com8/i Serial card >WD8003 ethernet card >With this config, I am only able to get 124K Bytes/sec. throughput under >Xenix. Under Dos I get 496 K Bytes/sec. Under ISC Unix, similar rates >to Dos. Is there a known problem with the scsi drivers under Xenix? >Why would throughput be so low? Running the same config except for the >drives and controller (substitue in a wd1003 controller and Maxtor 2190) >gave me double the disk throughput. Why??? Get the xnx252 driver from SCO or adaptex. You will see a performance gain. You could also check to see of the read ahead cache is enabled in the drive via SCSICNTL. If it isn't, try enabling it. Roy Neese Adaptec Senior SCSI Applications Engineer UUCP @ neese@adaptex uunet!cs.utexas.edu!utacfd!merch!adaptex!neese
jcurtis@simasd.uucp (Jay Curtis) (03/21/91)
In article <283400078@adaptx1> neese@adaptx1.UUCP writes: > >> I am having a problem with SCO Xenix 2.3.2GT and very low disk >>transfer rates. Here is my configuration: (stuff deleted) >>With this config, I am only able to get 124K Bytes/sec. throughput under >>Xenix. Under Dos I get 496 K Bytes/sec. Under ISC Unix, similar rates >>to Dos. Is there a known problem with the scsi drivers under Xenix? >>Why would throughput be so low? Running the same config except for the >>drives and controller (substitue in a wd1003 controller and Maxtor 2190) >>gave me double the disk throughput. Why??? > >Get the xnx252 driver from SCO or adaptex. You will see a performance gain. >You could also check to see of the read ahead cache is enabled in the drive >via SCSICNTL. If it isn't, try enabling it. > I am sorry. I forgot to tell you that the 124K was with xnx252 installed! Also the read ahead cache is enabled. I am in ASYNC mode as the other drive on the host adapter does not support SYNC transfers. When I tried enabling SYNC on the host adapter, the system would hang on bootup. Any other ideas? This is making me crazy! > Roy Neese > Adaptec Senior SCSI Applications Engineer > UUCP @ neese@adaptex > uunet!cs.utexas.edu!utacfd!merch!adaptex!neese --Jay -- Jay Curtis jcurtis@baron.UUCP {nosc;ncr-sd;ucsd;}!baron!jcurtis Of course my opinions are my own... Who would let me speak for them?!
goykhman_a@apollo.HP.COM (Alex Goykhman) (03/23/91)
In article <1991Mar21.055200.29525@simasd.uucp> jcurtis@simasd.uucp (Jay Curtis) writes: >In article <283400078@adaptx1> neese@adaptx1.UUCP writes: >> >>> I am having a problem with SCO Xenix 2.3.2GT and very low disk >>>transfer rates. Here is my configuration: >(stuff deleted) > >>>With this config, I am only able to get 124K Bytes/sec. throughput under >>>Xenix. Under Dos I get 496 K Bytes/sec. Under ISC Unix, similar rates >>>to Dos. Is there a known problem with the scsi drivers under Xenix? >>>Why would throughput be so low? Running the same config except for the >>>drives and controller (substitue in a wd1003 controller and Maxtor 2190) >>>gave me double the disk throughput. Why??? >> >>Get the xnx252 driver from SCO or adaptex. You will see a performance gain. >>You could also check to see of the read ahead cache is enabled in the drive >>via SCSICNTL. If it isn't, try enabling it. >> >I am sorry. I forgot to tell you that the 124K was with xnx252 >installed! Also the read ahead cache is enabled. I am in ASYNC mode as >the other drive on the host adapter does not support SYNC transfers. >When I tried enabling SYNC on the host adapter, the system would hang on >bootup. > >Any other ideas? This is making me crazy! Depending on the drive, ASYNC can cut the throughput by as much as 50%. Disconnect the second drive, and try the first one in the SYNC mode. PIO instead of DMA can lower throughput substantially, but not to 124Kb/sec. Finally, the drive have been formatted (FORMAT UNIT) with a ridiculously high interleave. >> Roy Neese >> Adaptec Senior SCSI Applications Engineer >> UUCP @ neese@adaptex >> uunet!cs.utexas.edu!utacfd!merch!adaptex!neese > > >--Jay >-- >Jay Curtis >jcurtis@baron.UUCP >{nosc;ncr-sd;ucsd;}!baron!jcurtis >Of course my opinions are my own... Who would let me speak for them?! Alex Goykhman P.S. The systems hangs with both the SYNC and ASYNC drives because the driver does not set the transfer mode properly, i.e. BEFORE the first REQ of a DATA IN/OUT phase. That should be easy to fix, so you might want to talk the developers. 496Kb/sec is a very low transfer rates, 124Mb/sec is laughable. Those developers should be ashamed of that kind of SCSI driver. ##############