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CSP: Correct spec to actually test for n processes (not 3)

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Nicholas Kariniemi 2015-12-11 14:32:23 +02:00
parent 2613f91510
commit 9901792fe8
1 changed files with 8 additions and 5 deletions
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13
spec/sync.csp
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@ -1,4 +1,4 @@
NUM_CLIENTS = 3
NUM_CLIENTS = 4
NUM_DB_STATES = 10
CLIENTS = {0..NUM_CLIENTS-1}
TIMES = {0..NUM_DB_STATES-1}
@ -56,9 +56,9 @@ assert SYSTEM :[divergence-free]
-- One way sync: changes on one client will sync to other client
-----------------------------------------
-- Suppose we limit our implemenetation to say that each
-- Suppose we limit our implementation to say that each
-- user makes a finite number of changes n.
MaxInputs(0) = STOP
MaxInputs(0) = SKIP
MaxInputs(n) = up?i?t -> MaxInputs(n-1)
-- Suppose we limit inputs to client 0.
@ -143,10 +143,13 @@ sequences(a) = {<z>^z' | z <- a, z' <- sequences(diff(a, {z}))}
renderAll(sequence, t) = ; i:sequence @ render!i.t -> SKIP
SyncAll(n) = |~| i:CLIENTS @ up!i!0 -> SyncThree'(n, n-1)
SyncAll'(n, 0) = |~| renderSeq:sequences(CLIENTS) @ renderAll(renderSeq, n)
SyncAll(n) = |~| i:CLIENTS @ up!i!0 -> SyncAll'(n, n-1)
SyncAll'(n, 0) = |~| renderSeq:sequences(CLIENTS) @ renderAll(renderSeq, n); STOP
SyncAll'(n, m) = |~| i:CLIENTS, t:TIMES @ up!i!t -> SyncAll'(n, m-1)
-- Number of changes allowed: 1, 5, 9
assert SyncAll(1) [FD= MaxInputSystem(1) \diff(Events, union(productions(up), {render.i.1 | i <- CLIENTS}))
assert SyncAll(5) [FD= MaxInputSystem(5) \diff(Events, union(productions(up), {render.i.5 | i <- CLIENTS}))
assert SyncAll(9) [FD= MaxInputSystem(9) \diff(Events, union(productions(up), {render.i.9 | i <- CLIENTS}))
-- This proves that given n clients, if we restrict them to x inputs total from any client in any order, eventually all n clients will render the same state i.e. they will be in sync.