David,

I was under the impression that "Anne & Lynn Wheeler" is in fact some sort of 
"Turing machine" inspired effort and not a real person at all.

It seems to get triggered every once in a while on certain keywords and then 
inserts a load of ancient history into the related post.....but then again that 
could describe quite a few board members :-)


Rob Scott
Rocket Software, Inc
275 Grove Street
Newton, MA 02466
617-614-2305
[EMAIL PROTECTED]


-----Original Message-----
From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of 
David Logan
Sent: 22 January 2008 14:34
To: [email protected]
Subject: Re: How does ATTACH pass address of ECB to child?

Sorry for the slightly off-topic question, but how come this persons posts are 
always so complicated to work through with all of the pieces and URL links? Is 
it the function of how they are posting (i.e. perhaps online with certain 
options), or is this a manual effort?

I'm hoping to not spark a long debate. I'm hoping it's just a "one or the 
other" answer.

David Logan

-----Original Message-----
From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of Anne 
& Lynn Wheeler
Sent: Tuesday, January 22, 2008 7:18 AM
To: [email protected]
Subject: Re: How does ATTACH pass address of ECB to child?

The following message is a courtesy copy of an article that has been posted to 
bit.listserv.ibm-main,alt.folklore.computers as well.

[EMAIL PROTECTED] (Peter Relson) writes:
> You can be certain that POST will always support the CS quick-post
protocol
> and the LOCAL LOCK.

re:
http://www.garlic.com/~lynn/2008b.html#50 How does ATTACH pass address of ECB 
to child?

as stated in the above post ... the principles of operation wording is from 
over 35yrs ago ... charlie had invented the compare&swap instruction at the 
science center while doing fine-grain lock for cp67 ... and the pok favorite 
son operating system people had rejected it ... i.e. the test&set was more than 
adequate for the global kernel spin-lock multiprocessor support from 360 ... 
mention of global spin-lock
http://www.garlic.com/~lynn/2008b.html#58 How does ATTACH pass address of ECB 
to child?

the challenge given the science center
http://www.garlic.com/~lynn/subtopic.html#545tech

was come up with example uses for compare&swap instruction ... other than
(multiprocessor) locking operation ... some discussion
http://www.garlic.com/~lynn/2008b.html#58 How does ATTACH pass address of ECB 
to child?

i.e. the compare&swap instruction can be used for atomic updates for whole 
class of operations w/o requiring "locking" operation (which would typically 
also require supervisor call into the kernel to have uninterruptable operation 
... as a means of simulating atomic update).
as mentioned in the above analogy with dbms financial transaction and 
optimistic operation ... that avoids lock ... if certain original conditions 
continue to hold when the transaction changes are actually made permanent.

so the wording in the principles of operation was from the stand-point that the 
pok favorite son operating system people still had to understand the 
implications of how compare&swap instruction could be used ... and then 
actually have the changes permeate their implementation.

my familiarity with cp67 dates back to when 3 people from the science center 
http://www.garlic.com/~lynn/subtopic.html#545tech
came out to install cp67 at the univ the last week of jan68 (40yrs ago this 
week)

one might claim that maybe that its time to update that 35+yr old perspective 
in the principles of operation compare&swap writeup.

A.6 Multiprogramming and Multiprocessing Examples 
http://publibz.boulder.ibm.com/cgi-bin/bookmgr_OS390/BOOKS/DZ9ZR003/A.6?SHEL
F=DZ9ZBK03&DT=20040504121320

other posts in this thread:
http://www.garlic.com/~lynn/2008b.html#31 How does ATTACH pass address of ECB 
to child?
http://www.garlic.com/~lynn/2008b.html#47 How does ATTACH pass address of ECB 
to child?
http://www.garlic.com/~lynn/2008b.html#48 How does ATTACH pass address of ECB 
to child?
http://www.garlic.com/~lynn/2008b.html#51 How does ATTACH pass address of ECB 
to child?
http://www.garlic.com/~lynn/2008b.html#60 How does ATTACH pass address of ECB 
to child?

for some topic drift ... related to dbms operation ... misc. posts about the 
original relational/sql project 
http://www.garlic.com/~lynn/subtopic.html#systemr

and transcriptions of '95 SQL reunion
http://www.mcjones.org/System_R/SQL_Reunion_95/index.html

there is mention of compare&swap in the discussion about use for "locking"
http://www.mcjones.org/System_R/SQL_Reunion_95/sqlr95-Shoot-ou.html#Index311
in this session:
http://www.mcjones.org/System_R/SQL_Reunion_95/sqlr95-Shoot-ou.html

however, the speculation about the origin of compare&swap instruction was wrong 
(i.e. compare&swap was chosen because CAS are charlie's initials).

----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions, send email to 
[EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at 
http://bama.ua.edu/archives/ibm-main.html

----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions, send email to 
[EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at 
http://bama.ua.edu/archives/ibm-main.html

----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO
Search the archives at http://bama.ua.edu/archives/ibm-main.html

Reply via email to