first round of fixes to cutoff

Author: Krastanov

src/ProtocolZoo/cutoff.jl

@@ -34,6 +34,7 @@ end
 
 @resumable function (prot::CutoffProt)()
     reg = prot.net[prot.node]
+<<<<<<< HEAD
     while true
         for slot in reg # TODO these should be done in parallel, otherwise we will be waiting on each slot, greatly slowing down the cutoffs
             islocked(slot) && continue
@@ -74,5 +75,57 @@ end
         else
             @yield timeout(prot.sim, prot.period::Float64)
         end
+=======
+    for slot in reg
+        @process per_slot_cutoff(prot.sim, slot, prot)
+    end
+end
+
+@resumable function per_slot_cutoff(sim, slot::RegRef, prot::CutoffProt)
+    empty_query = false
+    while true
+        if empty_query
+            if isnothing(prot.period)
+                @yield onchange_tag(slot) # TODO this should be just for the slot, not for the whole register
+            else
+                @yield timeout(prot.sim, prot.period::Float64)
+            end
+        end
+        @yield lock(slot)
+        info = query(slot, EntanglementCounterpart, ❓, ❓)
+        if isnothing(info)
+            empty_query = true
+            unlock(slot)
+            continue
+        end
+        println("$(now(sim)) $slot info $info")
+
+        if now(prot.sim) - info.time > prot.retention_time
+            untag!(slot, info.id)
+            traceout!(slot)
+            println("$(now(sim)) $slot traced out")
+            msg = Tag(EntanglementDelete, prot.node, slot.idx, info.tag[2], info.tag[3])
+            tag!(slot, msg)
+            (prot.announce) && put!(channel(prot.net, prot.node=>msg[4]; permit_forward=true), msg)
+            @debug "CutoffProt @$(prot.node): Send message to $(msg[4]) | message=`$msg` | time=$(now(prot.sim))"
+        end
+
+        # TODO the tag deletions below are not necessary when announce=true and EntanglementTracker is running on other nodes. Verify the veracity of that statement, make tests for both cases, and document.
+
+        # delete old history tags
+        info = query(slot, EntanglementHistory, ❓, ❓, ❓, ❓, ❓;filo=false) # TODO we should have a warning if `queryall` returns more than one result -- what does it even mean to have multiple history tags here
+        if !isnothing(info) && now(prot.sim) - info.time > prot.retention_time
+            untag!(slot, info.id)
+        end
+
+        # delete old EntanglementDelete tags
+        # TODO Why do we have separate entanglementhistory and entanglementupdate but we have only a single entanglementdelete that serves both roles? We should probably have both be pairs of tags, for consistency and ease of reasoning
+        info = query(slot, EntanglementDelete, prot.node, slot.idx , ❓, ❓) # TODO we should have a warning if `queryall` returns more than one result -- what does it even mean to have multiple delete tags here
+        if !isnothing(info) && now(prot.sim) - info.time > prot.retention_time
+            untag!(slot, info.id)
+        end
+
+        unlock(slot)
+>>>>>>> e5a26b4d (first round of fixes to cutoff)
     end
 end

src/queries.jl

@@ -363,15 +363,15 @@ tag!(tagcontainer, args...) = tag!(tagcontainer, Tag(args...))
 function _query(reg::RegOrRegRef, ::Val{allB}, ::Val{filoB}, query::Tag; locked::Union{Nothing,Bool}=nothing, assigned::Union{Nothing,Bool}=nothing) where {allB, filoB}
     ref = isa(reg, RegRef) ? reg : nothing
     reg = get_register(reg)
-    res = NamedTuple{(:slot, :id, :tag), Tuple{RegRef, Int128, Tag}}[]
+    res = NamedTuple{(:slot, :id, :tag, :time), Tuple{RegRef, Int128, Tag, Float64}}[]
     l = length(reg.guids)
     indices = filoB ? (l:-1:1) : (1:l)
     for i in indices
         i = reg.guids[i]
-        tag = reg.tag_info[i].tag
+        (;tag, time) = reg.tag_info[i]
         slot = reg[reg.tag_info[i].slot]
         if _nothingor(ref, slot) && _nothingor(locked, islocked(slot)) && _nothingor(assigned, isassigned(slot)) && tag==query
-            allB ? push!(res, (slot=slot, id=i, tag=tag)) : return (slot=slot, id=i, tag=tag)
+            allB ? push!(res, (;slot, id=i, tag, time)) : return (;slot, id=i, tag, time)
         end
     end
     allB ? res : nothing

test/test_protocolzoo_entanglement_tracker_grid.jl

@@ -229,6 +229,14 @@ end
 # More tests of 2D rectangular grids with the full stack of protocols,
 # but also now with an unlimited number of rounds and an entanglement consumer.
 
+using Test
+using Revise
+using ResumableFunctions
+using ConcurrentSim
+using QuantumSavory
+using QuantumSavory.ProtocolZoo
+using QuantumSavory.ProtocolZoo: EntanglementCounterpart, EntanglementHistory, EntanglementUpdateX, EntanglementUpdateZ
+using Graphs
 
 n = 6 # the size of the square grid network (n × n)
 regsize = 20 # the size of the quantum registers at each node
@@ -267,9 +275,10 @@ consumer = EntanglementConsumer(sim, net, 1, n^2)
 # at each node we discard the qubits that have decohered after a certain cutoff time
 for v in vertices(net)
     cutoffprot = CutoffProt(sim, net, v, retention_time=10, period=nothing)
-    @process cutoffprot()
+    #@process cutoffprot()
 end
-@test_broken (run(sim, 400); true)
+#@test_broken (run(sim, 400); true)
+run(sim, 400)
 
 for i in 1:length(consumer._log)
     @test consumer._log[i][2] ≈ 1.0