Talk:Peterson's algorithm

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Contents 1 Test and Set 2 External Links 3 Stub? 4 More information on Dutch page

[edit] Test and Set

As far as I know, test and set instructions have nothing to do with dual port RAM. tst have to do with the processor architecture, the bus arbiter, but not with the memory. For the time being, I will remove the link to dual port ram. Glipari (talk) 22:05, 25 January 2008 (UTC)

[edit] External Links

This External Link leads to a trivialization of Peterson's Algorithm.

It uses the AND operator and does not reset the flags. After the first run, which is interleafed, it reverts to serial runs, which is a trivialization of Peterson's original algorithm (1981). Using Peterson's original OR operator and resetting the flags as he does, every run is interleafed. These results have been checked by my research student, Ali Nademi, who has tested these runs using SPIN. Ali notes also that the run using the AND with no flag reset has no assertion violations. Even so, the interleafing stops after the first run. Since serial ordering of processes has no concurrency problem, there are no conflicts. Batch processing in serial order removes any need for the mutual exclusion algorithm, which is why we say that the AND version of Peterson's algorithm is a trivialization of the original intent.

GWO, 08-2005: I changed it back to the AND operator including a flag reset, because it didn't work as it was... Interleaving also seams to be fine now.

Earlier this month I provided a link to a Java application of Peterson's Algorithm, including source code. However, it was removed by 66.65.123.238. I've restored it for the time being until a justified reason for removal is given, such as the above statements which concern a different link that has long since been removed. -Stimpy 01:46, 27 November 2006 (UTC)

[edit] Stub?

Shouldn't this article be a stub? The actual algorithm itself isn't discussed anywhere...

[edit] More information on Dutch page

I came here from the Dutch page. Which gives a full formal proof (albeit in dutch) of the algorithm, and cites an english book (which I can verify, as I have it too). Also, is it really necessary to have an entire piece of C-code? Nice and fancy, but a very simple scetch(sp?) of the problem, and the proper solution should do just fine.