Ultrix-11
Warner Losh
imp at bsdimp.com
Fri Aug 20 11:20:57 CDT 2021
On Fri, Aug 20, 2021 at 9:50 AM Peter Allan via cctalk <
cctalk at classiccmp.org> wrote:
> How can I make a larger /usr partition? Is it possible to do this at
> installation time? There did not seem to be an option for this. Can it be
> done by using an additional disk? That would seem likely, but not what a
> system manager back in the 70's or 80's would expect to need to do,
> especially as there is a relatively large amount of space left to create
> /user1.
>
Ultrix-11 is old-school Unix. This means that it uses hard-wired partitions.
It's based on the controller that you use. So for an RD54 connected to an
RQDX3 would use the rq_sizes entry from dksizes.c:
/*
* Sizes for RD31/RD32/RD51/RD52/RD53/RD54/RX50/RX33 disks.
*/
struct rasize rq_sizes[8] = { /* RQDX1/RQDX2/RQDX3/RUX1 */
9700, 0, /* RD31-32,51-54 root (swap+error log -
rd51) */
17300, 9700, /* RD32/RD52/RD53/RD54 /usr */
3100, 27000, /* RD32/RD52/RD53/RD54 swap + error log */
-2, 30100, /* RD32/RD52/RD53/RD54 user files */
-2, 9700, /* RD51 /usr */
3100, 9700, /* RD31 swap + error log */
-2, 12800, /* RD31 /usr */
-1, 0, /* RD31-32, RD51-54 entire disk */
};
* Note - nblocks has two values with special meaning:
*
* An nblocks value of -1 specifies a partition length of
* the size of the entire disk minus the partition's
starting
* block number. In other words, the partition ends at the
* end of the disk.
*
* An nblocks value of -2 specifies a partition length of
* the size of the disk minus the size of the maintenance
* area minus the starting block number of the partition.
* In other words, the partition ends at the start of the
* maintenance area.
So a RD-54 is
* RD54
* +-----------------------+
* | 0 9700 root |
* | |
* +-----------------------+
* | 1 17300 /usr |
* | |
* | |
* +-----------------------+
* | 2 100 error log |
* | 3000 swap |
* +-----------------------+
* | 3 281068 user |
* | |
* | |
* | |
* +-----------------------+
* | 32 maintenance area |
* +-----------------------+
* 7 311200 (user = 311168)
*
and that's what you get. You could change the rq_sizes array, but that's
tricky to set up...
It's a lot easier to use a RA81 instead. It's 450MB instead of the 150MB
the RD54 in the
example and gives plenty of room.
You could also use a RA80 instead. It's a little smaller than the RD54 at
120MB, but it
as a 20,000 block /usr instead of the kinda tiny 17,200 block area of the
RD54. The RA60
is also an option at 200MB with the same 10MB /usr.
Warner
P.S. Kudos to the anonymous DEC employee that drew all the pictures for
each of
the supported disks in dksizes.
More information about the cctech
mailing list