diff --git a/src/net.cpp b/src/net.cpp
index 9ee6cb423c..926d570264 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -63,7 +63,7 @@ CCriticalSection cs_vNodes;
 map<CInv, CDataStream> mapRelay;
 deque<pair<int64, CInv> > vRelayExpiration;
 CCriticalSection cs_mapRelay;
-map<CInv, int64> mapAlreadyAskedFor;
+limitedmap<CInv, int64> mapAlreadyAskedFor(MAX_INV_SZ);
 
 static deque<string> vOneShots;
 CCriticalSection cs_vOneShots;
diff --git a/src/net.h b/src/net.h
index 368e4cd4bb..9cbb593f56 100644
--- a/src/net.h
+++ b/src/net.h
@@ -15,6 +15,7 @@
 #endif
 
 #include "mruset.h"
+#include "limitedmap.h"
 #include "netbase.h"
 #include "protocol.h"
 #include "addrman.h"
@@ -100,7 +101,7 @@ extern CCriticalSection cs_vNodes;
 extern std::map<CInv, CDataStream> mapRelay;
 extern std::deque<std::pair<int64, CInv> > vRelayExpiration;
 extern CCriticalSection cs_mapRelay;
-extern std::map<CInv, int64> mapAlreadyAskedFor;
+extern limitedmap<CInv, int64> mapAlreadyAskedFor;
 
 extern std::vector<std::string> vAddedNodes;
 extern CCriticalSection cs_vAddedNodes;
@@ -367,7 +368,12 @@ public:
     {
         // We're using mapAskFor as a priority queue,
         // the key is the earliest time the request can be sent
-        int64& nRequestTime = mapAlreadyAskedFor[inv];
+        int64 nRequestTime;
+        limitedmap<CInv, int64>::const_iterator it = mapAlreadyAskedFor.find(inv);
+        if (it != mapAlreadyAskedFor.end())
+            nRequestTime = it->second;
+        else
+            nRequestTime = 0;
         if (fDebugNet)
             printf("askfor %s   %"PRI64d" (%s)\n", inv.ToString().c_str(), nRequestTime, DateTimeStrFormat("%H:%M:%S", nRequestTime/1000000).c_str());
 
@@ -380,6 +386,10 @@ public:
 
         // Each retry is 2 minutes after the last
         nRequestTime = std::max(nRequestTime + 2 * 60 * 1000000, nNow);
+        if (it != mapAlreadyAskedFor.end())
+            mapAlreadyAskedFor.update(it, nRequestTime);
+        else
+            mapAlreadyAskedFor.insert(std::make_pair(inv, nRequestTime));
         mapAskFor.insert(std::make_pair(nRequestTime, inv));
     }