diff --git a/src/addrman.h b/src/addrman.h
index cabacbbea9..76e7b210f7 100644
--- a/src/addrman.h
+++ b/src/addrman.h
@@ -482,6 +482,7 @@ public:
     //! Return the number of (unique) addresses in all tables.
     size_t size() const
     {
+        LOCK(cs); // TODO: Cache this in an atomic to avoid this overhead
         return vRandom.size();
     }
 
@@ -501,13 +502,11 @@ public:
     //! Add a single address.
     bool Add(const CAddress &addr, const CNetAddr& source, int64_t nTimePenalty = 0)
     {
+        LOCK(cs);
         bool fRet = false;
-        {
-            LOCK(cs);
-            Check();
-            fRet |= Add_(addr, source, nTimePenalty);
-            Check();
-        }
+        Check();
+        fRet |= Add_(addr, source, nTimePenalty);
+        Check();
         if (fRet)
             LogPrint("addrman", "Added %s from %s: %i tried, %i new\n", addr.ToStringIPPort(), source.ToString(), nTried, nNew);
         return fRet;
@@ -516,14 +515,12 @@ public:
     //! Add multiple addresses.
     bool Add(const std::vector<CAddress> &vAddr, const CNetAddr& source, int64_t nTimePenalty = 0)
     {
+        LOCK(cs);
         int nAdd = 0;
-        {
-            LOCK(cs);
-            Check();
-            for (std::vector<CAddress>::const_iterator it = vAddr.begin(); it != vAddr.end(); it++)
-                nAdd += Add_(*it, source, nTimePenalty) ? 1 : 0;
-            Check();
-        }
+        Check();
+        for (std::vector<CAddress>::const_iterator it = vAddr.begin(); it != vAddr.end(); it++)
+            nAdd += Add_(*it, source, nTimePenalty) ? 1 : 0;
+        Check();
         if (nAdd)
             LogPrint("addrman", "Added %i addresses from %s: %i tried, %i new\n", nAdd, source.ToString(), nTried, nNew);
         return nAdd > 0;
@@ -532,23 +529,19 @@ public:
     //! Mark an entry as accessible.
     void Good(const CService &addr, int64_t nTime = GetAdjustedTime())
     {
-        {
-            LOCK(cs);
-            Check();
-            Good_(addr, nTime);
-            Check();
-        }
+        LOCK(cs);
+        Check();
+        Good_(addr, nTime);
+        Check();
     }
 
     //! Mark an entry as connection attempted to.
     void Attempt(const CService &addr, bool fCountFailure, int64_t nTime = GetAdjustedTime())
     {
-        {
-            LOCK(cs);
-            Check();
-            Attempt_(addr, fCountFailure, nTime);
-            Check();
-        }
+        LOCK(cs);
+        Check();
+        Attempt_(addr, fCountFailure, nTime);
+        Check();
     }
 
     /**
@@ -582,12 +575,10 @@ public:
     //! Mark an entry as currently-connected-to.
     void Connected(const CService &addr, int64_t nTime = GetAdjustedTime())
     {
-        {
-            LOCK(cs);
-            Check();
-            Connected_(addr, nTime);
-            Check();
-        }
+        LOCK(cs);
+        Check();
+        Connected_(addr, nTime);
+        Check();
     }
 
     void SetServices(const CService &addr, ServiceFlags nServices)
diff --git a/src/main.cpp b/src/main.cpp
index 067b394104..452ceac568 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -69,7 +69,7 @@ int64_t nTimeBestReceived = 0; // Used only to inform the wallet of when we last
 CWaitableCriticalSection csBestBlock;
 CConditionVariable cvBlockChange;
 int nScriptCheckThreads = 0;
-bool fImporting = false;
+std::atomic_bool fImporting(false);
 bool fReindex = false;
 bool fTxIndex = false;
 bool fHavePruned = false;
diff --git a/src/main.h b/src/main.h
index 43c62f6de6..c98ed05726 100644
--- a/src/main.h
+++ b/src/main.h
@@ -165,7 +165,7 @@ extern uint64_t nLastBlockWeight;
 extern const std::string strMessageMagic;
 extern CWaitableCriticalSection csBestBlock;
 extern CConditionVariable cvBlockChange;
-extern bool fImporting;
+extern std::atomic_bool fImporting;
 extern bool fReindex;
 extern int nScriptCheckThreads;
 extern bool fTxIndex;
diff --git a/src/net.cpp b/src/net.cpp
index ce87150ae3..ba74cd071e 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -1103,8 +1103,13 @@ void CConnman::ThreadSocketHandler()
                 }
             }
         }
-        if(vNodes.size() != nPrevNodeCount) {
-            nPrevNodeCount = vNodes.size();
+        size_t vNodesSize;
+        {
+            LOCK(cs_vNodes);
+            vNodesSize = vNodes.size();
+        }
+        if(vNodesSize != nPrevNodeCount) {
+            nPrevNodeCount = vNodesSize;
             if(clientInterface)
                 clientInterface->NotifyNumConnectionsChanged(nPrevNodeCount);
         }
diff --git a/src/net.h b/src/net.h
index a4a9fb676a..df3930d82e 100644
--- a/src/net.h
+++ b/src/net.h
@@ -615,7 +615,7 @@ public:
     const bool fInbound;
     bool fNetworkNode;
     bool fSuccessfullyConnected;
-    bool fDisconnect;
+    std::atomic_bool fDisconnect;
     // We use fRelayTxes for two purposes -
     // a) it allows us to not relay tx invs before receiving the peer's version message
     // b) the peer may tell us in its version message that we should not relay tx invs