ins_bjjb@jhunix.HCF.JHU.EDU (Jared Brennan) (07/30/89)
I've been having major speed problems with my ST251 drive (installed
in place of the Tandon 263 20Mb mechanism in my SH204). Like, it's really
slow, you know? Being too lazy to do anything about it, I waited a month,
then reformatted the drive. Before the reformat, the drive was interleaved
1:1, and returned a 383Kb/s transfer rate and 448ms access time using the
RATEHD program from ICD. After the reformat, at interleave 1:3 (or 3:1),
the transfer rate was 161Kb/s and 443ms access time. Hmmm...
A few questions for those experienced in these matters:
a) What is the relationship between the access time in RATEHD
and the manufacturer's specification of average seek time
(which is 40ms for the ST251)?
b) I have an ST251 from before the time when the ST251-1 was
introduced. Were there any major problems with this drive?
c) Could this have anything to do with using a very old version
of the Supra hard disk formatter (in which I must enter
the parameters of the drive by hand)?
d) (unrelated to the matter at hand) Are there any formatters
for the ST which allow you to enter the bad block list for
the hard drive by hand?
(Aside from this problem, I'm pretty well satisfied with the results
of replacing the drive in my SH204. Took only an hour or so for the
physical replacement (since I was probably over-cautious) and there
are no physical problems with the result. No major heat increase, no
power problems, and the heads park automatically when I power down the
drive.)
Thanks in advance for your assistance!
Jared Brennan <ins_bjjb@jhunix.hcf.jhu.edu> BITNET: INS_BJJB@JHUNIX,JHUVMS
ARPA: ins_bjjb%jhunix@hopkins.ARPA UUCP: allegra!hopkins!jhunix!ins_bjjb
"How many pins could one stick in the head of an angel?"
--
Jared Brennan <ins_bjjb@jhunix.hcf.jhu.edu> BITNET: INS_BJJB@JHUNIX,JHUVMS
ARPA: ins_bjjb%jhunix@hopkins.ARPA UUCP: allegra!hopkins!jhunix!ins_bjjb
"How many pins could one stick in the head of an angel?"ins_bjjb@jhunix.HCF.JHU.EDU (Jared Brennan) (07/31/89)
In article <2160@jhunix.HCF.JHU.EDU> I write: > I've been having major speed problems with my ST251 drive (installed >in place of the Tandon 263 20Mb mechanism in my SH204). Like, it's really >slow, you know? Being too lazy to do anything about it, I waited a month, >then reformatted the drive. Before the reformat, the drive was interleaved >1:1, and returned a 383Kb/s transfer rate and 448ms access time using the >RATEHD program from ICD. After the reformat, at interleave 1:3 (or 3:1), >the transfer rate was 161Kb/s and 443ms access time. Hmmm... > [questions deleted] Well, having nothing better to do after having taking all the software off my hard drive, I kept reformatting it and varying the parameters each time. When I changed the step pulse rate from its default value of 0 to 1 (or 2, or 3, or 4) in the Supra formatter, lo and behold! The access time dropped to 34ms. (As a side note, it was my impression that the drive was an ST251-0, 40ms access time. Looks like it's a ST251-1, rated 28ms. Gosh, and here I was thinking I had paid a good price for an ST251-0...) (-8 (-8 (-8 (-8 (-8 (-8 8-) 8-) 8-) 8-) 8-) 8-) ^^^ Did I mention that I was happy about this state of affairs? ^^^ Anyway, I would like to thank those of you who have sent replies to my request for help. Don't worry, next time I'll have a real humdinger for you, promise! 8-) -- Jared Brennan <ins_bjjb@jhunix.hcf.jhu.edu> BITNET: INS_BJJB@JHUNIX,JHUVMS ARPA: ins_bjjb%jhunix@hopkins.ARPA UUCP: allegra!hopkins!jhunix!ins_bjjb "How many pins could one stick in the head of an angel?"