Open VMS VAx 7.1 Mailbox index number

[Uwe Zessin]

Interesting, I would have bet that it was 32767. 'Magic values' based on 9s are usually used in an IBM environment, but my guess is that another 'optimization' was used:

-MBA9999:
-12345678

Again, 8 characters which nicely fit in a quadword. Is that right, Volker?

[labadie_1]

Uwe

The BG device have been limited to 9999 until Tcpip 5.4, where they can reach 32767

[Uwe Zessin]

BG devices cannot be compared with MBA devices, because they get cloned by a special kernel routine from BG0: (do a SHOW DEVICE and you'll see that it is a template). That routine did limit the unit number to 9999. Same with LTA devices, for example.

[Jan van den Ende]

Uwe,


That routine did limit the unit number to 9999. Same with LTA devices, for example.


Do I mis-read that, or did you phrase it inaccurate?

I tend to conclude from your text that LAT is also extended to LTA32767:, but under V7.3-2 it really still is LTA9999: (just tested that).

(not trying to solve serious problems, just curious)

fwiw,

Proost.

Have one on me.

jpe

[Uwe Zessin]

Hello Jan, welcome back.

No, I didn't intend to suggest that the LAT unit numbers were enhanced as well. I don't know and I don't try to track such details any longer.

[Volker Halle]

Uwe,

the UNIT number of a device is stored in the UCB in UCB$W_UNIT (a WORD). This field has just been expanded to a LONGWORD (UCB$L_UNIT) in V8.2 - you need a major release to do something like this.

Unit numbers on OpenVMS have 'always' been between 0 and 9999 (just checked the VAX/VMS IDSM, which is written based on V5.2).

There is even a bit in the V8.2 DEVICE_NAMING SYSGEN parameter to limit unit numbers to 10k: SGN$M_MAX_UNITS_10K (to retain the old behaviour).

I believe TCPIP BG devices were the driving force behind this change/expansion, as customers ran into this limitation on WEB servers.

Volker.

[Kris Clippeleyr]

Good morning guys,
According to my info, the increase from 9999 to 32767 is for BG and MBA devices only.
Greetz,
Kris (aka Qkcl)

[Rajarshi Gupta]

Guys,

I found in HP OpenVMS System Services Reference Manual of OVMS7.3-2 in the section $CREMBX

Mailboxes are assigned sequentially increasing numbers (from 1 to a maximum of 9999) as they are created. When all unit numbers have been used, the system starts numbering again at unit 1. Logical names or mailbox names should be used to identify a mailbox between cooperating processes.

In the follwing Link
http://h71000.www7.hp.com/doc/732FINAL/4527/4527pro_001.html#index_x_246

Could any body know about it.

[Volker Halle]

From OpenVMS V8.2 Release Notes:

http://h71000.www7.hp.com/DOC/82FINAL/6674/6674pro_sm.html

4.6 Device Unit Number Maximum Increased
V8.2

In the past, OpenVMS would never create more than 10,000 cloned device units, and unit numbers would wrap after 9999. This had become a limitation for some devices, such as mailboxes or TCP/IP sockets.

Starting with OpenVMS Version 7.3-2, OpenVMS will create up to 32,767 devices if the DEV$V_NNM bit is clear in UCB$L_DEVCHAR2 and if bit 2 is clear in the DEVICE_NAMING system parameter. This does not require any device driver change. However, programs and command procedures that are coded to assume a maximum device number of 9999 may need to be modified.


Volker.

[Rajarshi Gupta]

Guys,
Sub: PLOYCENTER to monitor contigious disk space.

Can any body known "Is it possible to monitor the contigous disk space in VAX VMS version 7.1 using POLYCENTER Monitoring tool"

Please provide the refernce link and case details if possible

thanks in advance