add a new option to helper_t, called HLP_OPT_CTONDMD, which will make…

… helper_t objects connect once the first call() attempt is made on them. This helps lessen the amount of dead connections that can be created and never used
OkCupid · Oct 11, 2012 · c5daee9 · c5daee9
1 parent bd9b38e
commit c5daee9
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Showing 3 changed files with 41 additions and 13 deletions.
diff --git a/libaok/ok.h b/libaok/ok.h
@@ -690,6 +690,8 @@ class dbcon_t : public helper_inet_t {
 public:
   dbcon_t (const rpc_program &g, const str &h, u_int p)
     : helper_inet_t (g, h, p, 0) {}
+  dbcon_t (const rpc_program &g, const str &h, u_int p, u_int o)
+    : helper_inet_t (g, h, p, o) {}
 
   str getname () const 
   { return strbuf ("database: ") << helper_inet_t::getname (); }

diff --git a/libpub/pslave.h b/libpub/pslave.h
@@ -47,6 +47,7 @@ typedef enum { HLP_STATUS_NONE = 0,
 #define HLP_OPT_PING    (1 << 1)        // ping helper on startup
 #define HLP_OPT_NORETRY (1 << 2)        // do not try to reconnect
 #define HLP_OPT_CNCT1   (1 << 3)        // connect only once on startup
+#define HLP_OPT_CTONDMD (1 << 4)        // connect on first call()
 
 #define HLP_MAX_RETRIES 100
 #define HLP_RETRY_DELAY 4
@@ -83,6 +84,7 @@ class helper_base_t {
 protected:
 };
 
+
 class helper_t : public helper_base_t {
 public:
   helper_t (const rpc_program &rp, u_int o = 0) 
@@ -92,6 +94,17 @@ class helper_t : public helper_base_t {
       retries (0), calls (0), status (HLP_STATUS_NONE), 
       opts (o), destroyed (New refcounted<bool> (false)) {}
 
+  struct connect_params_t {
+    connect_params_t(u_int32_t p, const void* i, void* o, aclnt_cb c,
+                     time_t d) : procno(p), in(i), out(o), cb(c), 
+                                 duration(d) { }
+    u_int32_t procno;
+    const void* in;
+    void* out;
+    aclnt_cb cb;
+    time_t duration;
+  };
+
   virtual ~helper_t ();
   virtual vec<str> *get_argv () { return NULL; }
   int getfd () const { return fd; }
@@ -130,7 +143,7 @@ class helper_t : public helper_base_t {
   void kill_aclnt_priv();
   void retried (ptr<bool> df, bool b);
   void connected (cbb::ptr cb, ptr<bool> df, bool b);
-
+  void call_connect_cb(connect_params_t cp, bool success);
 
   void process_queue ();
   void docall (u_int32_t procno, const void *in, void *out, aclnt_cb cb,

diff --git a/libpub/slave.C b/libpub/slave.C
@@ -274,21 +274,34 @@ helper_inet_t::launch_cb (cbb c, ptr<bool> df, int f)
     ping (c);
 }
 
+void
+helper_t::call_connect_cb(connect_params_t cp, bool success) {
+    if (!success) {
+        (*cp.cb)(RPC_PROCUNAVAIL);
+    } else 
+        docall(cp.procno, cp.in, cp.out, cp.cb, cp.duration);
+}
+
 void
 helper_t::call (u_int32_t procno, const void *in, void *out, aclnt_cb cb,
-		time_t duration)
-{
-  if (status != HLP_STATUS_OK || calls >= max_calls) {
-    if ((opts & HLP_OPT_QUEUE) && (status != HLP_STATUS_HOSED) && 
-	queue.size () < max_qlen) {
-      queue.push_back (New queued_call_t (procno, in, out, cb, duration));
-      return;
-    } else {
-      (*cb) (RPC_PROCUNAVAIL);
-      return;
+                time_t duration)
+{
+    if (status != HLP_STATUS_OK || calls >= max_calls) {
+        if ((opts & HLP_OPT_QUEUE) && (status != HLP_STATUS_HOSED) && 
+            queue.size () < max_qlen) {
+            queue.push_back (New queued_call_t (procno, in, out, cb, duration));
+            return;
+        } else if (opts & HLP_OPT_CTONDMD && status != HLP_STATUS_HOSED &&
+                   status != HLP_STATUS_RETRY) {
+            connect_params_t cp(procno, in, out, cb, duration);
+            connect( wrap(this, &helper_t::call_connect_cb, cp) );
+            return;
+        } else {
+            (*cb) (RPC_PROCUNAVAIL);
+            return;
+        }
     }
-  }
-  docall (procno, in, out, cb, duration);
+    docall (procno, in, out, cb, duration);
 }
 
 void