4.3BSD-UWisc/man/cat4/hk.4
HK(4) UNIX Programmer's Manual HK(4)
NAME
hk - RK6-11/RK06 and RK07 moving head disk
SYNOPSIS
controller hk0 at uba? csr 0177440 vector rkintr
disk rk0 at hk0 drive 0
DESCRIPTION
Files with minor device numbers 0 through 7 refer to various
portions of drive 0; minor devices 8 through 15 refer to
drive 1, etc. The standard device names begin with ``hk''
followed by the drive number and then a letter a-h for par-
titions 0-7 respectively. The character ? stands here for a
drive number in the range 0-7.
The block files access the disk via the system's normal
buffering mechanism and may be read and written without
regard to physical disk records. There is also a `raw'
interface which provides for direct transmission between the
disk and the user's read or write buffer. A single read or
write call results in exactly one I/O operation and there-
fore raw I/O is considerably more efficient when many words
are transmitted. The names of the raw files conventionally
begin with an extra `r.'
In raw I/O counts should be a multiple of 512 bytes (a disk
sector). Likewise _s_e_e_k calls should specify a multiple of
512 bytes.
DISK SUPPORT
The origin and size (in sectors) of the pseudo-disks on each
drive are as follows:
RK07 partitions:
disk start length cyl
hk?a 0 15884 0-240
hk?b 15906 10032 241-392
hk?c 0 53790 0-814
hk?d 25938 15884 393-633
hk?f 41844 11792 634-814
hk?g 25938 27786 393-813
RK06 partitions
disk start length cyl
hk?a 0 15884 0-240
hk?b 15906 11154 241-409
hk?c 0 27126 0-410
On a dual RK-07 system partition hk?a is used for the root
for one drive and partition hk?g for the /usr file system.
If large jobs are to be run using hk?b on both drives as
swap area provides a 10Mbyte paging area. Otherwise
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HK(4) UNIX Programmer's Manual HK(4)
partition hk?c on the other drive is used as a single large
file system.
FILES
/dev/hk[0-7][a-h] block files
/dev/rhk[0-7][a-h] raw files
SEE ALSO
hp(4), uda(4), up(4), syslogd(8)
DIAGNOSTICS
rk%d%c: hard error sn%d cs2=%b ds=%b er=%b. An unrecover-
able error occurred during transfer of the specified sector
of the specified disk partition. The contents of the cs2,
ds and er registers are printed in octal and symbolically
with bits decoded. The error was either unrecoverable, or a
large number of retry attempts (including offset positioning
and drive recalibration) could not recover the error.
rk%d: write locked. The write protect switch was set on the
drive when a write was attempted. The write operation is
not recoverable.
rk%d: not ready. The drive was spun down or off line when
it was accessed. The i/o operation is not recoverable.
rk%d: not ready (came back!). The drive was not ready, but
after printing the message about being not ready (which
takes a fraction of a second) was ready. The operation is
recovered if no further errors occur.
rk%d%c: soft ecc sn%d. A recoverable ECC error occurred on
the specified sector in the specified disk partition. This
happens normally a few times a week. If it happens more
frequently than this the sectors where the errors are occur-
ring should be checked to see if certain cylinders on the
pack, spots on the carriage of the drive or heads are indi-
cated.
hk%d: lost interrupt. A timer watching the controller
detected no interrupt for an extended period while an opera-
tion was outstanding. This indicates a hardware or software
failure. There is currently a hardware/software problem
with spinning down drives while they are being accessed
which causes this error to occur. The error causes a UNIBUS
reset, and retry of the pending operations. If the con-
troller continues to lose interrupts, this error will recur
a few seconds later.
BUGS
In raw I/O _r_e_a_d and _w_r_i_t_e(2) truncate file offsets to 512-
byte block boundaries, and _w_r_i_t_e scribbles on the tail of
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HK(4) UNIX Programmer's Manual HK(4)
incomplete blocks. Thus, in programs that are likely to
access raw devices, _r_e_a_d, _w_r_i_t_e and _l_s_e_e_k(2) should always
deal in 512-byte multiples.
DEC-standard error logging should be supported.
A program to analyze the logged error information (even in
its present reduced form) is needed.
The partition tables for the file systems should be read off
of each pack, as they are never quite what any single
installation would prefer, and this would make packs more
portable.
The rk07 g partition size in rk.c disagrees with that in
/etc/disktab.
Printed 12/27/86 June 1, 1986 3