From d5574ace2d557fa26013251d3a7a8e97769da5ce Mon Sep 17 00:00:00 2001
From: Jake Smith <jake.smith@lexisnexisrisk.com>
Date: Mon, 17 Jun 2024 18:15:55 +0100
Subject: [PATCH] HPCC-31627 Remove legacy central node delay

Some very old redundant code that was not being hit until
the HPCC-18382 changes were introduced caused random delays
when sockets were connecting in Thor.
This was spuriously seen when SORT was connecting merge
streams, introducing significant delays overall.

Signed-off-by: Jake Smith <jake.smith@lexisnexisrisk.com>
---
 system/jlib/jsocket.cpp       | 28 ++--------------------------
 system/jlib/jsocket.hpp       |  3 ---
 thorlcr/slave/thslavemain.cpp |  1 -
 3 files changed, 2 insertions(+), 30 deletions(-)

diff --git a/system/jlib/jsocket.cpp b/system/jlib/jsocket.cpp
index 962d328364b..9f4bb2d6b72 100644
--- a/system/jlib/jsocket.cpp
+++ b/system/jlib/jsocket.cpp
@@ -353,9 +353,6 @@ struct xfd_set { __fd_mask fds_bits[XFD_SETSIZE / __NFDBITS]; }; // define our o
 #define T_SOCKET int
 #define SEND_FLAGS (MSG_NOSIGNAL)
 #endif
-#ifdef CENTRAL_NODE_RANDOM_DELAY
-static SocketEndpointArray CentralNodeArray;
-#endif
 enum SOCKETMODE { sm_tcp_server, sm_tcp, sm_udp_server, sm_udp, sm_multicast_server, sm_multicast};
 
 #define BADSOCKERR(err) ((err==JSE_BADF)||(err==JSE_NOTSOCK))
@@ -1538,20 +1535,8 @@ void CSocket::connect_wait(unsigned timems)
     bool exit = false;
     int err;
     unsigned refuseddelay = 1;
-    while (!exit) {
-#ifdef CENTRAL_NODE_RANDOM_DELAY
-        ForEachItemIn(cn,CentralNodeArray) {
-            const SocketEndpoint &ep=CentralNodeArray.item(cn);
-            if (ep.ipequals(targetip)) {
-                unsigned sleeptime = getRandom() % 1000;
-                StringBuffer s;
-                ep.getHostText(s);
-                DBGLOG("Connection to central node %s - sleeping %d milliseconds", s.str(), sleeptime);
-                Sleep(sleeptime);           
-                break;
-            }
-        }
-#endif
+    while (!exit)
+    {
         unsigned remaining;
         exit = tm.timedout(&remaining);
         bool blockselect = exit;                            // if last time round block
@@ -6189,15 +6174,6 @@ ISocketBufferReader *createSocketBufferReader(const char *trc)
 }
 
 
-extern jlib_decl void markNodeCentral(SocketEndpoint &ep)
-{
-#ifdef CENTRAL_NODE_RANDOM_DELAY
-    CriticalBlock block(CSocket::crit);
-    CentralNodeArray.append(ep);
-#endif
-}
-
-
 static CSocket *prepareSocket(unsigned idx,const SocketEndpoint &ep, ISocketConnectNotify &inotify)
 {
     Owned<CSocket> sock = new CSocket(ep,sm_tcp,NULL);
diff --git a/system/jlib/jsocket.hpp b/system/jlib/jsocket.hpp
index 6587e9410ff..83c01639ef6 100644
--- a/system/jlib/jsocket.hpp
+++ b/system/jlib/jsocket.hpp
@@ -72,7 +72,6 @@ enum JSOCKET_ERROR_CODES {
 
 #ifndef _WIN32
 #define BLOCK_POLLED_SINGLE_CONNECTS  // NB this is much slower in windows
-#define CENTRAL_NODE_RANDOM_DELAY
 #else
 #define USERECVSEM      // to singlethread BF_SYNC_TRANSFER_PUSH
 #endif
@@ -633,8 +632,6 @@ interface ISocketBufferReader: extends IInterface
 
 extern jlib_decl ISocketBufferReader *createSocketBufferReader(const char *trc=NULL);
 
-extern jlib_decl void markNodeCentral(SocketEndpoint &ep); // random delay for linux
-
 interface ISocketConnectNotify
 {
 public:
diff --git a/thorlcr/slave/thslavemain.cpp b/thorlcr/slave/thslavemain.cpp
index 2f0c496a8cf..17bea9fb450 100644
--- a/thorlcr/slave/thslavemain.cpp
+++ b/thorlcr/slave/thslavemain.cpp
@@ -434,7 +434,6 @@ int main( int argc, const char *argv[]  )
         SocketEndpoint masterEp(master);
         localHostToNIC(masterEp);
         setMasterPortBase(masterEp.port);
-        markNodeCentral(masterEp);
 
         if (RegisterSelf(masterEp))
         {