Remove debt ratio

Rationale: selecting peers based on debt ratio in bytes
is no longer needed when the bandwidth for each chunk is
compensated.

dagger/bitswap.nim

@@ -43,8 +43,7 @@ type
     taskHandler: TaskHandler                     # handler provided by the engine called by the runner
 
 proc bitswapTaskRunner(b: Bitswap) {.async.} =
-  ## process tasks in order of least amount of
+  ## process tasks
-  ## debt ratio
   ##
 
   while b.bitswapRunning:

dagger/bitswap/engine.nim

@@ -87,25 +87,13 @@ proc requestBlocks*(
       blocks.add(
         b.pendingBlocks.addOrAwait(c).wait(timeout))
 
-  proc cmp(a, b: BitswapPeerCtx): int =
-    if a.debtRatio == b.debtRatio:
-      0
-    elif a.debtRatio > b.debtRatio:
-      1
-    else:
-      -1
 
-  # sort the peers so that we request
+  var peers = b.peers
-  # the blocks from a peer with the lowest
-  # debt ratio
-  var sortedPeers = b.peers.sorted(
-    cmp
-  )
 
   # get the first peer with at least one (any)
   # matching cid
   var blockPeer: BitswapPeerCtx
-  for i, p in sortedPeers:
+  for i, p in peers:
     let has = cids.anyIt(
       it in p.peerHave
     )
@@ -117,9 +105,9 @@ proc requestBlocks*(
   # didn't find any peer with matching cids
   # use the first one in the sorted array
   if isNil(blockPeer):
-    blockPeer = sortedPeers[0]
+    blockPeer = peers[0]
 
-  sortedPeers.keepItIf(
+  peers.keepItIf(
     it != blockPeer
   )
 
@@ -130,7 +118,7 @@ proc requestBlocks*(
     cids,
     wantType = WantType.wantBlock) # we want this remote to send us a block
 
-  if sortedPeers.len == 0:
+  if peers.len == 0:
     return blocks # no peers to send wants to
 
   template sendWants(ctx: BitswapPeerCtx) =
@@ -141,10 +129,10 @@ proc requestBlocks*(
       wantType = WantType.wantHave) # we only want to know if the peer has the block
 
   # filter out the peer we've already requested from
-  var stop = sortedPeers.high
+  var stop = peers.high
   if stop > b.peersPerRequest: stop = b.peersPerRequest
   trace "Sending want list requests to remaining peers", count = stop + 1
-  for p in sortedPeers[0..stop]:
+  for p in peers[0..stop]:
     sendWants(p)
 
   return blocks

dagger/bitswap/peercontext.nim

@@ -15,10 +15,7 @@ type
   BitswapPeerCtx* = ref object of RootObj
     id*: PeerID
     peerPrices*: Table[Cid, UInt256] # remote peer have list including price
-    peerHave*: seq[Cid]         # remote peers have lists
     peerWants*: seq[Entry]      # remote peers want lists
-    bytesSent*: int             # bytes sent to remote
-    bytesRecv*: int             # bytes received from remote
     exchanged*: int             # times peer has exchanged with us
     lastExchange*: Moment       # last time peer has exchanged with us
     pricing*: ?Pricing          # optional bandwidth price for this peer
@@ -30,12 +27,6 @@ proc contains*(a: openArray[BitswapPeerCtx], b: PeerID): bool =
 
   a.anyIt( it.id == b )
 
-proc debtRatio*(b: BitswapPeerCtx): float =
-  b.bytesSent / (b.bytesRecv + 1)
-
-proc `<`*(a, b: BitswapPeerCtx): bool =
-  a.debtRatio < b.debtRatio
-
 func updatePresence*(context: BitswapPeerCtx, presence: Presence) =
   let cid = presence.cid
   let price = presence.price

tests/dagger/bitswap/testengine.nim

@@ -185,99 +185,6 @@ suite "Bitswap engine handlers":
       check peerCtx.peerHave.contains(cid)
       check peerCtx.peerPrices[cid] == price
 
-suite "Bitswap engine blocks":
-
-  let
-    rng = Rng.instance()
-    chunker = newRandomChunker(Rng.instance(), size = 2048, chunkSize = 256)
-    blocks = chunker.mapIt( bt.Block.new(it) )
-    wallet = WalletRef.example
-
-  var
-    engine: BitswapEngine
-    peersCtx: seq[BitswapPeerCtx]
-    peers: seq[PeerID]
-    done: Future[void]
-
-  setup:
-    done = newFuture[void]()
-    engine = BitswapEngine.new(MemoryStore.new(), wallet)
-    peersCtx = @[]
-
-    for i in 0..3:
-      let seckey = PrivateKey.random(rng[]).tryGet()
-      peers.add(PeerID.init(seckey.getKey().tryGet()).tryGet())
-
-      peersCtx.add(BitswapPeerCtx(
-        id: peers[i]
-      ))
-
-    # set debt ratios
-
-    # ratio > 1
-    peersCtx[0].bytesSent = 1000
-    peersCtx[0].bytesRecv = 100
-
-    # ratio < 1
-    peersCtx[1].bytesSent = 100
-    peersCtx[1].bytesRecv = 1000
-
-    # ratio > 1
-    peersCtx[2].bytesSent = 100
-    peersCtx[2].bytesRecv = 99
-
-    # ratio == 0
-    peersCtx[3].bytesSent = 100
-    peersCtx[3].bytesRecv = 100
-
-    engine.peers = peersCtx
-
-  test "should select peer with least debt ratio":
-    proc sendWantList(
-      id: PeerID,
-      cids: seq[Cid],
-      priority: int32 = 0,
-      cancel: bool = false,
-      wantType: WantType = WantType.wantHave,
-      full: bool = false,
-      sendDontHave: bool = false) {.gcsafe.} =
-        check cids == blocks.mapIt( it.cid )
-        if peersCtx[1].id == id: # second peer has the least debt ratio
-          check wantType == WantType.wantBlock
-          engine.resolveBlocks(blocks)
-        else:
-          check wantType == WantType.wantHave
-
-    engine.request.sendWantList = sendWantList
-
-    let pending = engine.requestBlocks(blocks.mapIt( it.cid ))
-    let resolved = await allFinished(pending)
-    check resolved.mapIt( it.read ) == blocks
-
-  test "should select peer with least debt ratio and have CIDs":
-    proc sendWantList(
-      id: PeerID,
-      cids: seq[Cid],
-      priority: int32 = 0,
-      cancel: bool = false,
-      wantType: WantType = WantType.wantHave,
-      full: bool = false,
-      sendDontHave: bool = false) {.gcsafe.} =
-        check cids == blocks.mapIt( it.cid )
-        if peersCtx[3].id == id: # 4th peer has the least debt ratio and has cids
-          check wantType == WantType.wantBlock
-          engine.resolveBlocks(blocks)
-        else:
-          check wantType == WantType.wantHave
-
-    engine.request.sendWantList = sendWantList
-
-    peersCtx[3].peerHave = blocks.mapIt( it.cid )
-    let pending = engine.requestBlocks(blocks.mapIt( it.cid ))
-    let resolved = await allFinished(pending)
-    check resolved.mapIt( it.read ) == blocks
-
-
 suite "Task Handler":
 
   let