gwoho@nntp-server.caltech.edu (g liu) (02/17/91)
i have tried a half dozen programs to llf a ide drive--all of them pretend to llformat it, none of them really do. also i am interested in adjusting the interleave. there are a number of programs i have tried that pretend to adjust the interleave too. people say that this should not need to be done and its already 1:1. it is not 1:1 on my drive. its 2:1. i would like to know how to adjust it so i can make it best for whatever os i use. it would be dumb if ide drives are stuck at 1:1 for a lot of people, because they run os that can not keep up. some people have reported destroying their ide drives via llformating. apparently their programs were not just pretending to llformat; they must really have been doing it. would one of those people email me a copy of the program? thankyou in advance. gwoho liu.
sigma@jec302.its.rpi.edu (Kevin J Martin) (02/18/91)
gwoho@nntp-server.caltech.edu (g liu) writes: >people say that this should not need to be done and its already 1:1. >it is not 1:1 on my drive. its 2:1. i would like to know how to adjust it >so i can make it best for whatever os i use. >it would be dumb if ide drives are stuck at 1:1 for a lot of people, because >they run os that can not keep up. The OS shouldn't make any difference to the interleave, and vice versa. As I understand it, the real bottleneck on transferring data from the disk to the computer is the bus. The processor itself is usually going to be faster than any of that already. >some people have reported destroying their ide drives via llformating. >apparently their programs were not just pretending to llformat; they must >really have been doing it. would one of those people email me a copy of >the program? Let me get this straight. You're ASKING someone to send you a copy of the program which rendered their IDE drive USELESS, so you can try it too?! On the face of it, it sounds insane. What sort of data transfer rate are you getting? I mean, as tested by a program like CheckIt or something. -- Kevin Martin sigma@rpi.edu
gwoho@nntp-server.caltech.edu (g liu) (02/18/91)
In comp.sys.ibm.pc.hardware you write: >gwoho@nntp-server.caltech.edu (g liu) writes: >>people say that this should not need to be done and its already 1:1. >>it is not 1:1 on my drive. its 2:1. i would like to know how to adjust it >>so i can make it best for whatever os i use. >>it would be dumb if ide drives are stuck at 1:1 for a lot of people, because >>they run os that can not keep up. >The OS shouldn't make any difference to the interleave, and vice versa. As >I understand it, the real bottleneck on transferring data from the disk to >the computer is the bus. The processor itself is usually going to be >faster than any of that already. this depends on what machine you have. my drive has 34 sectors/track, spins at 60/sec so at 1:1, it sends about 1m/sec. my card wount do dma, so the 286 has to get the data itself. the 286 does a rep movs to get the data. that takes 4 cycles/byte. so, at 6mhz, the cpu is spending most of its time moving data. it has no time to do any processing to get ready to recieve the next sector by the time it comes around. some oss use more time than others, so 1:1 wont work for some oss. >>some people have reported destroying their ide drives via llformating. >>apparently their programs were not just pretending to llformat; they must >>really have been doing it. would one of those people email me a copy of >>the program? >Let me get this straight. You're ASKING someone to send you a copy of the >program which rendered their IDE drive USELESS, so you can try it too?! On >the face of it, it sounds insane. >What sort of data transfer rate are you getting? I mean, as tested by a >program like CheckIt or something. it messed up their drive--i dont think it will mess up mine. i believe they have to send the right information to the drive to get it to substitute the right blocks to make it work right. for example, to get my scsi drive to work well, i had to send it the following bytes: 4 16 0 0 2 0 0 0 0 4 0 0 0 129. i am willing to mess with the drive, sending it random codes to make it work. its not as hard as it may seem. >-- >Kevin Martin >sigma@rpi.edu
mso@media01.UUCP (Manfred Sonsma) (02/18/91)
> [deleted] > What sort of data transfer rate are you getting? I mean, as tested by a > program like CheckIt or something. > I have 'low level' formatted my Quantum Prodrive 115AT several times with the FORMAT option of the AMI bios diagnostic menu and with Zenith's PREP utility. The AMI bios does a check for the best interleave factor by checking the transfer rate for each factor starting with an interleave 1:1. The first time I run it selected 1:3. The second time it decided to use an interleave of 1:1. However the transfer rate did remain the same. About 759 Kb/s. Tested with CORETEST I get the following transfer rates: 801 Kb/Sec with 64 Kb blocks 1134 Kb/Sec with 32 Kb blocks. ( The maximum ) Checkit returns a lower value: 563 Kb/Sec with 130 Kb blocks. [That's way I love CORETEST] The problem is that I don't known the transfer rate before the format. Does anyone ??? Furthermore, does any one know how to program the Quantum drive. I have read somewhere that you can program the cache strategy used by the drive. Manfred. * _/) * * / / * __ __ _/ /_____________ * ___ _\==/_ Me __________(_) - - - Manfred Sonsma - - - ||___) { o__o } Bug ___) Mediasystemen B.V. +- / Me \ -+ Buster ___) mso@media01.UUCP +-| Bug |-+ -\________) Tel: +31-23-319075 / Fax: +31-23-315210 +-\ _____/-+ -> The Nobel price for he/she who brings CED to the UNIX command line. <-