Fix master lease time

Author: QiumingLu

include/skywalker/checkpoint.h

@@ -29,11 +29,6 @@ class Checkpoint {
   virtual bool LoadCheckpoint(uint32_t group_id, uint64_t instance_id,
                               uint32_t machine_id, const std::string& dir,
                               const std::vector<std::string>& files);
-
- private:
-  // No copying allowed
-  Checkpoint(const Checkpoint&);
-  void operator=(const Checkpoint&);
 };
 
 }  // namespace skywalker

include/skywalker/state_machine.h

@@ -24,10 +24,6 @@ class StateMachine {
 
  private:
   uint32_t id_;
-
-  // No copying allowed
-  StateMachine(const StateMachine&);
-  void operator=(const StateMachine&);
 };
 
 }  // namespace skywalker

machine/master_machine.cc

@@ -27,7 +27,7 @@ void MasterMachine::Recover() {
 }
 
 bool MasterMachine::Execute(uint32_t group_id, uint64_t instance_id,
-                            const std::string& value, void* /* context */) {
+                            const std::string& value, void* context) {
   MasterState state;
   if (state.ParseFromString(value)) {
     if (instance_id < state_.version()) {
@@ -37,7 +37,12 @@ bool MasterMachine::Execute(uint32_t group_id, uint64_t instance_id,
     int ret = config_->GetDB()->SetMasterState(state);
     if (ret == 0) {
       bool b = (state.node_id() != state_.node_id());
-      state.set_lease_time(NowMicros() + state.lease_time());
+      uint64_t* now = reinterpret_cast<uint64_t*>(context);
+      if (now) {
+        state.set_lease_time(*now + state.lease_time());
+      } else {
+        state.set_lease_time(NowMicros() + state.lease_time());
+      }
       SetMasterState(state);
       LOG_INFO(
           "Group %u - now the master's version=%llu, "

machine/master_machine.h

@@ -33,7 +33,7 @@ class MasterMachine : public StateMachine {
   void SetString(const std::string& s);
 
   virtual bool Execute(uint32_t group_id, uint64_t instance_id,
-                       const std::string& value, void* /* context */);
+                       const std::string& value, void* context);
 
  private:
   Config* config_;

paxos/group.cc

@@ -18,8 +18,9 @@ Group::Group(uint64_t node_id, uint32_t group_id, const GroupOptions& options,
       config_(node_id, group_id, options, network),
       instance_(&config_),
       use_master_(options.use_master),
-      lease_timeout_(options.master_lease_time),
       retrie_master_(false),
+      lease_timeout_(options.master_lease_time),
+      now_(0),
       mutex_(),
       cond_(&mutex_),
       propose_end_(false),
@@ -126,11 +127,12 @@ void Group::TryBeMaster() {
 
 void Group::TryBeMasterInLoop() {
   MasterState state(master_machine_->GetMasterState());
-  if (state.lease_time() <= NowMicros() || state.node_id() == node_id_) {
+  now_ = NowMicros();
+  if (state.lease_time() <= now_ || state.node_id() == node_id_) {
     state.set_node_id(node_id_);
     state.set_lease_time(lease_timeout_);
     instance_.OnPropose(master_machine_->machine_id(),
-                        state.SerializeAsString());
+                        state.SerializeAsString(), &now_);
   } else {
     propose_cb_(instance_.GetInstanceId(),
                 Status::Conflict("Already has master"), nullptr);

paxos/group.h

@@ -72,8 +72,9 @@ class Group {
   Instance instance_;
 
   bool use_master_;
-  uint64_t lease_timeout_;
   bool retrie_master_;
+  uint64_t lease_timeout_;
+  uint64_t now_;
   MembershipMachine* membership_machine_;
   MasterMachine* master_machine_;
   ProposeCompleteCallback propose_cb_;