COS418-Assignment 2 Chandy-Lamport Distributed Snapshots Solved

In this  you will implement the Chandy-Lamport algorithm for distributed snapshots. Your snapshot algorithm will be implemented on top of a token passing system, similar to the ones presented in Precept 4 and in the Chandy-Lamport paper.

The algorithm makes the following assumptions:

There are no failures and all messages arrive intact and only once
The communication channels are unidirectional and FIFO ordered
There is a communication path between any two processes in the system
Any process may initiate the snapshot algorithm
The snapshot algorithm does not interfere with the normal execution of the processes
Each process in the system records its local state and the state of its incoming channels
Software
You will find the code under this directory. The code is organized as follows:

server.go: A process in the distributed algorithm
simulator.go: A discrete time simulator
logger.go: A logger that records events executed by system (useful for debugging)
common.go: Debug flag and common message types used in the server, logger, and simulator
snapshot_test.go: Tests you need to pass
syncmap.go: Implementation of thread-safe map
queue.go: Simple queue interface implemented using lists in Go
test_common.go: Helper functions for testing
test_data/: Test case inputs and expected results
Of these files, you only need to turn in server.go and simulator.go. However, some other files also contain information that will be useful for your implementation or debugging, such as the debug flag in common.go and the thread-safe map in syncmap.go. Your task is to implement the functions that say TODO: IMPLEMENT ME, adding fields to the surrounding classes if necessary.


$ cd chandy-lamport/
$ go test
Running test '2nodes.top', '2nodes-simple.events'
Running test '2nodes.top', '2nodes-message.events'
Running test '3nodes.top', '3nodes-simple.events'
Running test '3nodes.top', '3nodes-bidirectional-messages.events'
Running test '8nodes.top', '8nodes-sequential-snapshots.events'
Running test '8nodes.top', '8nodes-concurrent-snapshots.events'
Running test '10nodes.top', '10nodes.events'
PASS
ok _/path/to/chandy-lamport 0.012s
To run individual tests, you can look up the test names in snapshot_test.go and run:

$ go test -run 2Node
Running test '2nodes.top', '2nodes-simple.events'
Running test '2nodes.top', '2nodes-message.events'
PASS
ok chandy-lamport 0.006s

$ git commit -am "[you fill me in]"
$ git tag -a -m "i finished assignment 2" a2-handin
$ git push origin master
$ git push origin a2-handin