1 files changed, 56 insertions, 0 deletions

diff --git a/src/rpc.cpp b/src/rpc.cpp
index 23e25ef..df7ca05 100644
--- a/src/rpc.cpp
+++ b/src/rpc.cpp
@@ -2596,6 +2596,18 @@ static void LocalAcceptFn(void*)
                 break;
             continue;
         }
+        // #6: let the OS probe a peer that has gone silent, so a half-open
+        // session eventually errors out of recv and lands in the event
+        // loop's existing reap path instead of sitting in gMiners forever.
+        // This is a backstop, not the mechanism: the default cadence before
+        // the first probe is hours on most stacks, so the idle timeout in
+        // PoolEventLoop fires long before keepalive does. Miners arriving
+        // via a relay ride a loopback socket pair whose remote transport is
+        // the rendezvous socket owned by the tunnel pump threads; keepalive
+        // cannot reach across that, which is part of why the idle timeout
+        // exists.
+        int keepalive = 1;
+        setsockopt(c, SOL_SOCKET, SO_KEEPALIVE, (char*)&keepalive, sizeof(keepalive));
         LogPrint("pool", "[pool] miner arrived via loopback -- pushing to event loop\n");
         PushReady((btf_socket_t)c);
     }
@@ -2639,6 +2651,16 @@ static const int64 POOL_ACTIVE_WINDOW     = 300; // a miner is "active" if it
 static const int64 POOL_UNAUTH_GRACE_SECS = 60;  // a connection still not
                                                  // authorized after this long is
                                                  // idle, not merely starting up
+// #6: a Miner used to leave gMiners only when RecvLine reported a clean
+// disconnect. A half-open session (miner host died, NAT state expired,
+// cable pulled) sends no FIN and reports no error, so it sat in the table
+// forever -- authorize outpaced disconnect 2:1 on the live pool, and the
+// table grew toward MAX_POOL_MINERS, past which real miners are refused.
+// lastSeen is stamped on every complete line received; a miner that has
+// said nothing for this long is gone in every way that matters. Ten
+// minutes is far beyond the vardiff target (a share every 15s) and the
+// stall watchdog (45s), so no miner that is actually hashing comes close.
+static const int64 POOL_IDLE_TIMEOUT_SECS = 600;
 
 // Non-blocking recv: pull whatever bytes are available now into buf, then
 // return one complete line if one is ready. Three outcomes:
@@ -4940,6 +4962,35 @@ static void PoolEventLoop()
             m->hashRate *= pow(0.5, (silent - grace) / expected);
         }
 
+        // 3.7. Idle reap (#6). Mirror the clean-disconnect path exactly --
+        // log, close, erase from gMiners via std::find, delete -- just with
+        // a different reason. Shares the miner already earned stay in
+        // roundShareCount, exactly as they do when a miner cleanly
+        // disconnects mid-round. connectTime stands in for lastSeen on a
+        // connection that never completed a line. Erasing inside the loop
+        // above would invalidate the iteration, so collect then reap.
+        {
+            int64 now = GetTime();
+            std::vector<Miner*> idle;
+            for (Miner* m : gMiners) {
+                int64 last = (m->lastSeen > 0) ? m->lastSeen : m->connectTime;
+                if (now - last > POOL_IDLE_TIMEOUT_SECS)
+                    idle.push_back(m);
+            }
+            for (Miner* m : idle) {
+                LogPrint("worker", "[pool] dropping idle miner %s -- nothing"
+                         " received in over %llds (session shares: %llu,"
+                         " round shares: %llu)\n",
+                         m->worker.empty() ? "(never authorized)" : m->worker.c_str(),
+                         (long long)POOL_IDLE_TIMEOUT_SECS,
+                         (unsigned long long)m->sessionShares,
+                         (unsigned long long)m->roundShares);
+                sock_close(m->fd);
+                gMiners.erase(std::find(gMiners.begin(), gMiners.end(), m));
+                delete m;
+            }
+        }
+
         // 4. Select over miner sockets
         if (!gMiners.empty()) {
             fd_set fds; FD_ZERO(&fds);
@@ -4962,6 +5013,11 @@ static void PoolEventLoop()
                     // terminate the whole node -- not just the pool. Every
                     // line arrives from an unauthenticated socket.
                     while (RecvLine(m->fd, m->readBuf, line, disc)) {
+                        // Any complete line is proof of life (#6): authorize
+                        // and valid shares already stamp lastSeen themselves,
+                        // but a miner that only ever subscribes (or sends
+                        // unrecognised methods) must count as alive too.
+                        m->lastSeen = GetTime();
                         try {
                             HandleLine(m, line, roundShareCount,
                                        roundShareTotal, blocksFoundThisSession);