Sequential Consistency Paper Reading

Lamport 1979 paper is often cited when talking about sequential consistency [1].  
But the paper context is outdated. Robert Morris gives the following 
requirements which are together equivalent to IR1 and IR2 [2]:
IR1: Every processor issues memory requests in the order specified by its program.
IR2:Memory requests from all processors issued to an individual memory module are 
    serviced from a single FIFO queue. Issuing a memory request consists of entering
    the request on this queue.


Lamport paper from 1979 shows system is seq consistent if:
 1. each machine executes one op at a time, waiting for it to complete
 2. executes ops on each mem location one at a time

[1][How to Make a Multiprocessor Computer That Correctly Executes Multiprocess
   Programs] 
   http://research.microsoft.com/en-us/um/people/lamport/pubs/multi.pdf
[2] http://pdos.csail.mit.edu/6.824-2012/notes/l06.txt

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