T.R | Title | User | Personal Name | Date | Lines |
---|
176.1 | Change mrd_res_size... | COOKIE::MRU | | Sun Sep 15 1996 12:00 | 13 |
176.2 | concerned..... | COOKIE::BOONE | | Mon Sep 16 1996 08:51 | 5 |
176.3 | | NABETH::alan | Dr. File System's Home for Wayward Inodes. | Mon Sep 16 1996 12:51 | 7 |
176.4 | | COOKIE::BOONE | | Tue Sep 17 1996 08:45 | 3 |
176.5 | | NABETH::alan | Dr. File System's Home for Wayward Inodes. | Thu Sep 26 1996 16:40 | 8 |
176.6 | | NABETH::alan | Dr. File System's Home for Wayward Inodes. | Mon Jan 27 1997 11:48 | 18 |
| Part of the V1.2 work, was to add fields and support to calculate
the maximum number of elements for given I/O size limit. The direct
connect SCSI size limit is 65535. The limit for command disk connect
SCSI is 8192. If status for more elements than this are requested
through mrd_read_element_status, another routine is called to
break down the request into chunks the right size. This data is
mapped back into the Read Element Status format for use by the
caller.
I ran an extensive test with the parameters adjusted so that a
direct connect SCSI could pretend to be a command disk connected
robot and the results were the same for V1.1 and the new code
in V1.2. A test of the true direct connect SCSI is only possible
in a five tower TL82x configuration; 65535 bytes of data is enough
for 1,213 slots.
Some detail testing of the error path is needed, but this is
basically done.
|
176.7 | Command disk data region size may vary | COOKIE::KYLER | | Mon Jan 27 1997 13:54 | 8 |
| > The limit for command disk connect SCSI is 8192.
Note that while this may be true for every known command disk
implementation, the size is not architecturally specified. The MSCSIP
spec designates a field in the command disk Global Information Region
(LBN 0) which specifies the size of the Data Region in 512 byte units.
- Dan.
|
176.8 | Close. | NABETH::alan | Dr. File System's Home for Wayward Inodes. | Mon Jan 27 1997 14:10 | 1 |
| All done.
|
176.9 | | NABETH::alan | Dr. File System's Home for Wayward Inodes. | Mon Jan 27 1997 18:59 | 1 |
| Point me at the field and I'll fix it.
|
176.10 | data_region_size | COOKIE::KYLER | | Tue Jan 28 1997 13:27 | 34 |
| > Point me at the field and I'll fix it.
The field is "data_region_size" in the typedef'ed struct "gir_buffer_t"
in mrd_vms.c.
From MSCSIP spec:
The Global Information Region consists of a single sector at LBN 0 of
the Command Disk. It contains data of the form:
+-----------------+-----------------+-----------------+--------------+
| ASCII code for "I am a Command Disk!" (20 bytes) | : 0
| ... | -16
+-----------------+-----------------+-----------------+--------------+
| Subsidiary Unit Number | MSCSIP vers num | Server State | :20
+-----------------+-----------------+-----------------+--------------+
| SCSI INQUIRY data for device, obtained with EVPD = 0 (36 bytes) | :24
| ... | -56
+-----------------+-----------------+-----------------+--------------+
| Reserved | Config Flags | Data Region sz in 512-byte blks| :60
+-----------------+-----------------+-----------------+--------------+
^
/|\
/ | \
/ | \
|
|
|
This Field
|
176.11 | Done. Really. | SSDEVO::ROLLOW | Dr. File System's Home for Wayward Inodes. | Thu Jan 30 1997 08:22 | 2 |
| It took an extra field in robot_info_t, but I now get the
command disk size from the command disk.
|