Subject: Survival Tips + QIC table
To: None <port-pc532@sun-lamp.cs.berkeley.edu>
From: Julian Howard Stacey <Julian.Howard.Stacey@regent.e-technik.tu-muenchen.de>
List: port-pc532
Date: 07/20/1994 20:56:42
Tip 1:
Have a /var dir. , (not a /var --> /usr/var like I used to.)
Reason 1:
I was crashing regularly when doing a
cd /usr/src make
at exactly the same point:
===> libc
cc -O -DYP -DLIBC_SCCS -DSYSLIBC_SCCS
-DPOSIX_MISTAKE -c
/usr/src.940715/lib/libc/db/btree/bt_close.c
Until ... finally the kernel wouldnt boot, &
I paid more attention to my boot errs:
cd: can't cd to /var/run
runtime link editor directory cache
/var/run/ld.so.hints: No such file or directory
building databases...
kvm_mkdb: /var/run//kvm_netbsd.tmp: No such file or directory
dev_mkdb: /var/run//dev.tmp: No such file or directory
Tip 2:
Hang some 10s of K of sacrificial data on end of tape tars,
Reason 2:
I recently found that the driver when reading tapes silently discards
last valid bit of data (see previous posting)
Tip 3:
Ensure your tape image is an even multiple of the tape track length
Reason 3:
Stuart suspects the driver times out during rewind, & system then
subsequently crashes system, this is only a suspicion so far,
but if correct, this means quantising tape contents
near as possible to beginning of tape (ie 2 tracks, 4 tracks, or 6 etc),
for a 45M DC300XL tape, on 10, 20, 30M etc boundaries.
(PS credit to Stuart if suspicion proven correct,
rotten eggs to me if premature publicity of unfounded suspicion ;-)
So that you can all calculate your track length here's a table I compiled
a few months back: (need a wide screen to view)
===
TAPE-PRODUCT SIZE MEGBYTS FEET OERSTED TRACKS FTPI BPI IPS QIC COMMENT
===================================================================================================
Datalife DL300 29 300 310 4 1600
-----------------------------------------------------------------------------------------------------
BASF 300XLP Full 45 450 310 9 10000 8000 90 11,24
SONY QD-300XL/P 45 137m2 310 9 6400-10K 30-90 (Max10K BPI
PCS DC300XL/P Full 450 310 9 10000 PCS man isctl
Scoth DC300XL
(Sun-3) 11 terry@cs.weber.edu
-----------------------------------------------------------------------------------------------------
BASF 300XPL/600 Full 60 620 310 9 10000 8000 90 11,24 On request
-----------------------------------------------------------------------------------------------------
Datalife DL450 25 450 310 9 6400
Datalife DL450ECT 45 450 310 9 10000
-----------------------------------------------------------------------------------------------------
PCS DC600A Full ? 600 550 15 12500 PCS man isctl
DC600A Full 25 ? ? ? ? ? ? ? PerifairCipher
3M DC600A ~90 600 550 12500 gj@pcs.dec.com
3M DC600A 64.4 600 550 12500 testblock.c
-----------------------------------------------------------------------------------------------------
BASF 600A Full 60 620 550 9 10000 8000 120 24
SONY QD-600A & XTD 60/150 182m9 550 9/18 12500 90-120 (Max10K BPI
PCS DC600XTD Full 600 550 18 12500 PCS man isctl
-----------------------------------------------------------------------------------------------------
Datalife DL600EXL 60 620 310 9 10000
-----------------------------------------------------------------------------------------------------
Datalife DL600 60/125 620 550 9-15MB 12500
-----------------------------------------------------------------------------------------------------
Datalife DL600ECT 150 620 550 18 12500
-----------------------------------------------------------------------------------------------------
BASF 6150 Full 120/150 620 550 15/18 12500 10000 120 120,150
PCS DC6150 Full 600 550 18 12500 PCS man isctl
Datalife DL6150 150 620 550 32 12500
6150 Full 25 ? ? ? ? ? ? ? PerifairCipher
-----------------------------------------------------------------------------------------------------
BASF 6250 Full 250 1020 550 18 12500 10000 120 150
PCS DC6250 Full 1000 550 18 12500 PCS man isctl
Datalife DL6250 250 1020 550 32
-----------------------------------------------------------------------------------------------------
BASF 6320 Full 320 620 550 26 20000 16000 120 525
PCS DC6320 Full 600 550 26 20000 PCS man isctl
Datalife DL6320 320 620 550 26 20000
-----------------------------------------------------------------------------------------------------
BASF 6525 Full 525 1020 550 26 20000 16000 120 525
Datalife DL6525 525 1020 550 26 20000
PCS DC6525 Full 1000 550 26 20000 PCS man isctl
-----------------------------------------------------------------------------------------------------
BASF 9100 Full 1000 760 900 30 45000 36000 120 1000 Q4-91
BASF 9135 Full 1350 760 900 30 38750 51667 120 1350 Q4-91
===================================================================================================
TAPE_PRODUCT Product name such as QIC525
SIZE Mini:Length=3.188",Width=2.415,Height=0.470; Full Size:Length=6",Width=4,Height=0.675
MEGBYTS Nominal Capacity in Megabytes
FEET Tape Length in feet
OERSTED Coercitivity
TRACKS Tracks max
FTPI Recording Density (max) (Flux Transitions/Inch ? )
BPI Recording Density (max) ( ??? / Inch ? )
IPS Tape Speed Max (Inches/Second)
QIC Associated QIC Standard
COMMENT
===================================================================================================
Datalife DL1000(10MB) 10 185 550 12 10000
Datalife DL1000(20MB) 20 185 550 12 10000
-----------------------------------------------------------------------------------------------------
BASF 2000 Mini 40 205 550 20 10000 10000 90 40,100
Datalife DL2000 40 205 550 24 12500
SONY QD-2000 40 62m5 550 24 12500 50-72 (Max10K BPI
-----------------------------------------------------------------------------------------------------
BASF 2000XL Mini 60 307.5 550 20 10000 10000 90 40,100 On request
Datalife DL2000XL 60 300 550 24 12500
-----------------------------------------------------------------------------------------------------
BASF 2080 Mini 80 205 550 32 14700 14700 90 80
Datalife DL2080 80 205 550 32 15000
-----------------------------------------------------------------------------------------------------
BASF 2110 Mini 110 205 550 32 20000 16000 90 128 On request
BASF 2120 Mini 120 307.5 550 32 14700 14700 90 80
BASF 2165 Mini 165 307.5 550 32 20000 16000 90 2110 On request
BASF 2380 Mini 380 230 900 40 38700 51667 90 380 Q4-91
===================================================================================================
===
--
Julian Stacey <stacey@freefall.cdrom.com>
Alternates: <julian@pcsbst.pcs.com>,<jhs@regent.e-technik.tu-muenchen.de>
Tel. +49 89 268616 TZ=GMT+1 Munich, Germany
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