Touch the oldest completed slice when marking a burrow for liquidation

e2e/main.py

@@ -541,7 +541,7 @@ def call_bulk(bulks, *, batch_size, profiler=general_gas_profiler):
                 )
                 for burrow_no in burrows
             ],
-            batch_size=40,
+            batch_size=32,
             profiler=mark_for_liquidation_profiler,
         )
 

src/checker.ml

@@ -289,48 +289,6 @@ let entrypoint_set_burrow_delegate (state, (burrow_no, delegate_opt): checker *
   assert_checker_invariants state;
   ([op], state)
 
-let[@inline] entrypoint_mark_for_liquidation (state, burrow_id: checker * burrow_id) : (LigoOp.operation list * checker) =
-  assert_checker_invariants state;
-  let _ = ensure_no_tez_given () in
-  let burrow = find_burrow state.burrows burrow_id in
-
-  let
-    { liquidation_reward = liquidation_reward;
-      collateral_to_auction = collateral_to_auction;
-      burrow_state = burrow;
-    } = match burrow_request_liquidation state.parameters burrow with
-    | None ->
-      (* Note: disabling coverage for the unreported but accessed right-hand side;
-       * accessibility is sufficiently marked on the pattern itself. *)
-      ((Ligo.failwith error_NotLiquidationCandidate [@coverage off]): liquidation_details)
-    | Some type_and_details -> let _, details = type_and_details in details
-  in
-
-  let state =
-    if eq_tok_tok collateral_to_auction tok_zero then
-      (* If the slice would be empty, don't create it. *)
-      { state with burrows = Ligo.Big_map.update burrow_id (Some burrow) state.burrows; }
-    else
-      (* Otherwise do. *)
-      let contents =
-        { burrow = burrow_id;
-          tok = collateral_to_auction;
-          min_kit_for_unwarranted = compute_min_kit_for_unwarranted state.parameters burrow collateral_to_auction;
-        } in
-      let (updated_liquidation_auctions, _leaf_ptr) =
-        liquidation_auction_send_to_auction state.liquidation_auctions contents in
-      { state with
-        burrows = Ligo.Big_map.update burrow_id (Some burrow) state.burrows;
-        liquidation_auctions = updated_liquidation_auctions;
-      } in
-
-  let op = match (LigoOp.Tezos.get_entrypoint_opt "%burrowSendTezTo" (burrow_address burrow): (Ligo.tez * Ligo.address) Ligo.contract option) with
-    | Some c -> LigoOp.Tezos.tez_address_transaction (tez_of_tok liquidation_reward, !Ligo.Tezos.sender) (Ligo.tez_from_literal "0mutez") c
-    | None -> (Ligo.failwith error_GetEntrypointOptFailureBurrowSendTezTo : LigoOp.operation) in
-
-  assert_checker_invariants state;
-  ([op], state)
-
 (* Cancel the liquidation of a slice. *)
 let entrypoint_cancel_liquidation_slice (state, leaf_ptr: checker * leaf_ptr) : (LigoOp.operation list * checker) =
   assert_checker_invariants state;
@@ -359,7 +317,7 @@ let entrypoint_cancel_liquidation_slice (state, leaf_ptr: checker * leaf_ptr) :
 (* Note that this function prepends the operation to the list of operations
  * given. This means that if we entrypoint_touch a list of liquidation slices,
  * the order of operations is reversed. *)
-let touch_liquidation_slice
+let[@inline] touch_liquidation_slice
     (ops: LigoOp.operation list)
     (auctions: liquidation_auctions)
     (state_burrows: burrow_map)
@@ -453,6 +411,83 @@ let touch_liquidation_slice
     | None -> (Ligo.failwith error_GetEntrypointOptFailureBurrowSendSliceToChecker : LigoOp.operation) in
   ((op :: ops), auctions, state_burrows, state_parameters, state_fa2_state)
 
+let[@inline] entrypoint_mark_for_liquidation (state, burrow_id: checker * burrow_id) : (LigoOp.operation list * checker) =
+  assert_checker_invariants state;
+  let _ = ensure_no_tez_given () in
+
+  let
+    { burrows = state_burrows;
+      cfmm = state_cfmm;
+      parameters = state_parameters;
+      liquidation_auctions = state_liquidation_auctions;
+      last_price = state_last_price;
+      fa2_state = state_fa2_state;
+      external_contracts = state_external_contracts;
+    } = state in
+
+  let burrow = find_burrow state_burrows burrow_id in
+
+  let
+    { liquidation_reward = liquidation_reward;
+      collateral_to_auction = collateral_to_auction;
+      burrow_state = burrow;
+    } = match burrow_request_liquidation state_parameters burrow with
+    | None ->
+      (* Note: disabling coverage for the unreported but accessed right-hand side;
+       * accessibility is sufficiently marked on the pattern itself. *)
+      ((Ligo.failwith error_NotLiquidationCandidate [@coverage off]): liquidation_details)
+    | Some type_and_details -> let _, details = type_and_details in details
+  in
+
+  let state_burrows = Ligo.Big_map.update burrow_id (Some burrow) state_burrows in
+
+  let state_liquidation_auctions =
+    if eq_tok_tok collateral_to_auction tok_zero then
+      (* If the slice would be empty, don't create it. *)
+      state_liquidation_auctions
+    else
+      (* Otherwise do. *)
+      let contents =
+        { burrow = burrow_id;
+          tok = collateral_to_auction;
+          min_kit_for_unwarranted = compute_min_kit_for_unwarranted state_parameters burrow collateral_to_auction;
+        } in
+      let (state_liquidation_auctions, _leaf_ptr) =
+        liquidation_auction_send_to_auction state_liquidation_auctions contents in
+      state_liquidation_auctions
+  in
+
+  let op = match (LigoOp.Tezos.get_entrypoint_opt "%burrowSendTezTo" (burrow_address burrow): (Ligo.tez * Ligo.address) Ligo.contract option) with
+    | Some c -> LigoOp.Tezos.tez_address_transaction (tez_of_tok liquidation_reward, !Ligo.Tezos.sender) (Ligo.tez_from_literal "0mutez") c
+    | None -> (Ligo.failwith error_GetEntrypointOptFailureBurrowSendTezTo : LigoOp.operation) in
+  let ops = [op] in
+
+  (* Touch the oldest liquidation slice (if it exists). This should help the
+   * system keep the number of liquidation slices close to linear in many
+   * occasions. *)
+  let ops, state_liquidation_auctions, state_burrows, state_parameters, state_fa2_state =
+    match liquidation_auction_oldest_completed_liquidation_slice state_liquidation_auctions with
+    | None ->
+      ops, state_liquidation_auctions, state_burrows, state_parameters, state_fa2_state
+    | Some leaf ->
+      let ops, state_liquidation_auctions, state_burrows, state_parameters, state_fa2_state =
+        touch_liquidation_slice ops state_liquidation_auctions state_burrows state_parameters state_fa2_state leaf in
+      ops, state_liquidation_auctions, state_burrows, state_parameters, state_fa2_state
+  in
+
+  let state =
+    { burrows = state_burrows;
+      cfmm = state_cfmm;
+      parameters = state_parameters;
+      liquidation_auctions = state_liquidation_auctions;
+      last_price = state_last_price;
+      fa2_state = state_fa2_state;
+      external_contracts = state_external_contracts;
+    } in
+
+  assert_checker_invariants state;
+  (ops, state)
+
 (* NOTE: The list of operations returned is in reverse order (with respect to
  * the order the input slices were processed in). However, since the operations
  * computed are independent from each other, this needs not be a problem. *)