diff --git a/dali/base/dacoven.cpp b/dali/base/dacoven.cpp
index 9f2e08e7bc8..1ba5324da8c 100644
--- a/dali/base/dacoven.cpp
+++ b/dali/base/dacoven.cpp
@@ -331,10 +331,10 @@ class CCovenBase: implements ICoven, public CInterface
         return comm->barrier();
     }
 
-    virtual bool verifyConnection(rank_t rank, unsigned timeout=1000*60*5)
+    virtual bool verifyConnection(rank_t rank, unsigned timeout=1000*60*5, bool allowConnect=true)
     {
         assertex(comm);
-        return comm->verifyConnection(rank,timeout);
+        return comm->verifyConnection(rank,timeout, allowConnect);
     }
 
 
@@ -768,10 +768,10 @@ class CCovenServer: public CCovenBase
         updateDataStore();
     }
 
-    virtual bool send (CMessageBuffer &mbuf, rank_t dstrank, mptag_t tag, unsigned timeout=MP_WAIT_FOREVER, bool skipDisconnected=false)
+    virtual bool send (CMessageBuffer &mbuf, rank_t dstrank, mptag_t tag, unsigned timeout=MP_WAIT_FOREVER)
     {
         assertex(comm);
-        return comm->send(mbuf,dstrank,tag,timeout,skipDisconnected);
+        return comm->send(mbuf,dstrank,tag,timeout);
     }
 
     bool sendRecv(CMessageBuffer &mbuff, rank_t sendrank, mptag_t sendtag, unsigned timeout=MP_WAIT_FOREVER)
@@ -912,11 +912,11 @@ class CCovenClient: public CCovenBase
         assertex(!"setInitSDSNodes not allowed in client");
     }
 
-    virtual bool send (CMessageBuffer &mbuf, rank_t dstrank, mptag_t tag, unsigned timeout=MP_WAIT_FOREVER, bool skipDisconnected=false)
+    virtual bool send (CMessageBuffer &mbuf, rank_t dstrank, mptag_t tag, unsigned timeout=MP_WAIT_FOREVER)
     {
         assertex(comm);
         try {
-            return comm->send(mbuf,dstrank,tag,timeout,skipDisconnected);
+            return comm->send(mbuf,dstrank,tag,timeout);
         }
         CATCH_MPERR_link_closed
     }
diff --git a/system/mp/mpcomm.cpp b/system/mp/mpcomm.cpp
index d8fa817ad27..cf38e87afe9 100644
--- a/system/mp/mpcomm.cpp
+++ b/system/mp/mpcomm.cpp
@@ -2981,7 +2981,7 @@ class CCommunicator: public ICommunicator, public CInterface
     IMPLEMENT_IINTERFACE;
 
 
-    bool send (CMessageBuffer &mbuf, rank_t dstrank, mptag_t tag, unsigned timeout, bool skipDisconnected)
+    bool send (CMessageBuffer &mbuf, rank_t dstrank, mptag_t tag, unsigned timeout)
     { 
         // send does not corrupt mbuf
         if (dstrank==RANK_NULL)
@@ -2996,7 +2996,7 @@ class CCommunicator: public ICommunicator, public CInterface
             CTimeMon tm(timeout);
             rank_t endrank;
             if (dstrank==RANK_ALL) {
-                send(mbuf,myrank,tag,timeout,false);
+                send(mbuf,myrank,tag,timeout);
                 dstrank = RANK_ALL_OTHER;
             }
             if (dstrank==RANK_ALL_OTHER) {
@@ -3023,8 +3023,6 @@ class CCommunicator: public ICommunicator, public CInterface
                     unsigned remaining;
                     if (tm.timedout(&remaining))
                         return false;
-                    if (skipDisconnected && !channel->isConnected())
-                        continue;
                     if (!channel->send(mbuf,tag,mbuf.getReplyTag(),tm,false))
                         return false;
                 }
@@ -3065,7 +3063,7 @@ class CCommunicator: public ICommunicator, public CInterface
 
             mb.clear();
             mb.append("MPTAG_BARRIER");
-            bool oks = send(mb,dst,MPTAG_BARRIER,120000,false);
+            bool oks = send(mb,dst,MPTAG_BARRIER,120000);
             mb.clear();
             bool okr = recv(mb,src,MPTAG_BARRIER,&r);
 
@@ -3083,7 +3081,7 @@ class CCommunicator: public ICommunicator, public CInterface
 #endif
     }
 
-    bool verifyConnection(rank_t rank,  unsigned timeout)
+    bool verifyConnection(rank_t rank,  unsigned timeout, bool allowConnect=true)
     {
         CriticalBlock block(verifysect);
         assertex(rank!=RANK_RANDOM);
@@ -3093,7 +3091,7 @@ class CCommunicator: public ICommunicator, public CInterface
         unsigned remaining;
         if (tm.timedout(&remaining))
             return false;
-        return channel->verifyConnection(tm,true);
+        return channel->verifyConnection(tm,allowConnect);
     }
 
     bool verifyAll(bool duplex, unsigned totalTimeout, unsigned perConnectionTimeout)
@@ -3273,7 +3271,7 @@ class CCommunicator: public ICommunicator, public CInterface
         unsigned remaining;
         if (tm.timedout(&remaining))
             return false;
-        if (!send(mbuff,sendrank,sendtag,remaining,false)||tm.timedout(&remaining))
+        if (!send(mbuff,sendrank,sendtag,remaining)||tm.timedout(&remaining))
             return false;
         mbuff.clear();
         return recv(mbuff,sendrank,replytag,NULL,remaining);
@@ -3284,7 +3282,7 @@ class CCommunicator: public ICommunicator, public CInterface
         mptag_t replytag = mbuf.getReplyTag();
         rank_t dstrank = group->rank(mbuf.getSender());
         if (dstrank!=RANK_NULL) {
-            if (send (mbuf, dstrank, replytag,timeout,false)) {
+            if (send (mbuf, dstrank, replytag,timeout)) {
                 mbuf.setReplyTag(TAG_NULL);
                 return true;
             }
diff --git a/system/mp/mpcomm.hpp b/system/mp/mpcomm.hpp
index f242758a4be..4825640e071 100644
--- a/system/mp/mpcomm.hpp
+++ b/system/mp/mpcomm.hpp
@@ -34,7 +34,7 @@ const unsigned MPVerboseMsgThreshold = 110; // greater than default logging deta
 
 interface ICommunicator: extends IInterface
 {
-    virtual bool send (CMessageBuffer &mbuf, rank_t dstrank, mptag_t tag, unsigned timeout=MP_WAIT_FOREVER, bool skipDisconnected=false) = 0;  
+    virtual bool send (CMessageBuffer &mbuf, rank_t dstrank, mptag_t tag, unsigned timeout=MP_WAIT_FOREVER) = 0;  
                             // blocking send (unless MP_ASYNC_SEND used for timeout), NB, mbuf clear on exit
                             // returns false if timedout
 
@@ -54,7 +54,7 @@ interface ICommunicator: extends IInterface
 
     virtual void flush  (mptag_t tag) = 0;    // flushes pending buffers
 
-    virtual bool verifyConnection(rank_t rank, unsigned timeout=1000*60*5) = 0; // verifies connected to rank
+    virtual bool verifyConnection(rank_t rank, unsigned timeout=1000*60*5, bool allowConnect=true) = 0; // verifies connected to rank
     virtual bool verifyAll(bool duplex=false, unsigned timeout=1000*60*30, unsigned perConnectionTimeout=0) = 0;
     virtual void disconnect(INode *node) = 0;
     virtual void barrier() = 0;
diff --git a/thorlcr/graph/thgraphmaster.cpp b/thorlcr/graph/thgraphmaster.cpp
index 71a8e64e7c3..bc87c51f4d9 100644
--- a/thorlcr/graph/thgraphmaster.cpp
+++ b/thorlcr/graph/thgraphmaster.cpp
@@ -17,6 +17,9 @@
 
 #include <limits.h>
 #include <stdlib.h>
+#include <future>
+#include <vector>
+#include <iterator>
 #include "jprop.hpp"
 #include "jexcept.hpp"
 #include "jiter.ipp"
@@ -1599,7 +1602,7 @@ void CJobMaster::freeMPTag(mptag_t tag)
     }
 }
 
-void CJobMaster::broadcast(ICommunicator &comm, CMessageBuffer &msg, mptag_t mptag, unsigned timeout, const char *errorMsg, CReplyCancelHandler *msgHandler, bool sendOnly, bool skipDisconnected)
+void CJobMaster::broadcast(ICommunicator &comm, CMessageBuffer &msg, mptag_t mptag, unsigned timeout, const char *errorMsg, CReplyCancelHandler *msgHandler, bool sendOnly, bool aborting)
 {
     unsigned groupSizeExcludingMaster = comm.queryGroup().ordinality() - 1;
 
@@ -1609,45 +1612,29 @@ void CJobMaster::broadcast(ICommunicator &comm, CMessageBuffer &msg, mptag_t mpt
         replyTag = queryJobChannel(0).queryMPServer().createReplyTag();
         msg.setReplyTag(replyTag);
     }
-    if (globals->getPropBool("@broadcastSendAsync", true)) // only here in case of problems/debugging.
-    {
-        class CSendAsyncfor : public CAsyncFor
-        {
-            CMessageBuffer &msg;
-            mptag_t mptag;
-            unsigned timeout;
-            StringAttr errorMsg;
-            ICommunicator &comm;
-            bool skipDisconnected;
-        public:
-            CSendAsyncfor(ICommunicator &_comm, CMessageBuffer &_msg, mptag_t _mptag, unsigned _timeout, const char *_errorMsg, bool _skipDisconnected)
-                : comm(_comm), msg(_msg), mptag(_mptag), timeout(_timeout), errorMsg(_errorMsg), skipDisconnected(_skipDisconnected)
-            {
-            }
-            void Do(unsigned i)
-            {
-                if (!comm.send(msg, i+1, mptag, timeout, skipDisconnected))
-                    throw createBCastException(i+1, errorMsg);
-            }
-        } afor(comm, msg, mptag, timeout, errorMsg, skipDisconnected);
-        try
+    std::vector<std::future<std::pair<unsigned, bool>>> sendResultsFuture;
+    for (unsigned i=0; i<groupSizeExcludingMaster; i++)
+        if (comm.verifyConnection(i+1, (unsigned)-1, !aborting))
         {
-            afor.For(groupSizeExcludingMaster, groupSizeExcludingMaster);
+            sendResultsFuture.push_back(
+                std::async([&, i]
+                {
+                    return std::make_pair(i+1, comm.send(msg, i+1, mptag, timeout));
+                })
+            );
         }
-        catch (IException *e)
+    for (auto & sendResultFuture: sendResultsFuture)
+    {
+        auto result = sendResultFuture.get();
+        if (result.second==false)
         {
+            IException * e = createBCastException(result.first, errorMsg);
             EXCLOG(e, "broadcastSendAsync");
             abort(e);
-            throw;
+            throw e;
         }
     }
-    else if (!comm.send(msg, RANK_ALL_OTHER, mptag, timeout, skipDisconnected))
-    {
-        Owned<IException> e = createBCastException(0, errorMsg);
-        EXCLOG(e, NULL);
-        abort(e);
-        throw e.getClear();
-    }
+
     if (sendOnly) return;
     unsigned respondents = 0;
     Owned<IBitSet> bitSet = createThreadSafeBitSet();
diff --git a/thorlcr/graph/thgraphmaster.ipp b/thorlcr/graph/thgraphmaster.ipp
index 307ab39b3b8..9b7b7d7a21d 100644
--- a/thorlcr/graph/thgraphmaster.ipp
+++ b/thorlcr/graph/thgraphmaster.ipp
@@ -173,7 +173,7 @@ public:
     void registerFile(const char *logicalName, StringArray &clusters, unsigned usageCount=0, WUFileKind fileKind=WUFileStandard, bool temp=false);
     void deregisterFile(const char *logicalName, bool kept=false);
     const SocketEndpoint &queryAgentEp() const { return agentEp; }
-    void broadcast(ICommunicator &comm, CMessageBuffer &msg, mptag_t mptag, unsigned timeout, const char *errorMsg, CReplyCancelHandler *msgHandler=NULL, bool sendOnly=false, bool skipDisconnected=false);
+    void broadcast(ICommunicator &comm, CMessageBuffer &msg, mptag_t mptag, unsigned timeout, const char *errorMsg, CReplyCancelHandler *msgHandler=NULL, bool sendOnly=false, bool aborting=false);
     IPropertyTree *prepareWorkUnitInfo();
     void sendQuery();
     void jobDone();