On Fri, Aug 20, 2021 at 9:50 AM Peter Allan via cctalk < cctalk@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.