Shared memory support. The shared memory is inside

apache scoreboard. If it ever gets back ported we could use it on 2.0

Submitted by: mturk

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@104617 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/modules/proxy/mod_proxy.h b/modules/proxy/mod_proxy.h
index 73bdec121df045c59e092ef2b50595977a7d735f..9e808b4ada6ac33aa46d7568cf51d3f931c975ad 100644 (file)
--- a/modules/proxy/mod_proxy.h
+++ b/modules/proxy/mod_proxy.h
@@ -256,12 +256,18 @@ struct proxy_worker {
 
 /* Runtime worker status informations. Shared in scoreboard */
 typedef struct {
-    proxy_balancer  *b;         /* balancer containing this worker */
-    proxy_worker    *w;
-    double          lbfactor;   /* dynamic lbfactor */
+    int             id;         /* scoreboard id */
     double          lbstatus;   /* Current lbstatus */
+    double          lbfactor;   /* dynamic lbfactor */
     apr_size_t      transfered; /* Number of bytes transfered to remote */
     apr_size_t      readed;     /* Number of bytes readed from remote */
+} proxy_runtime_stat;
+
+/* Runtime worker. */
+typedef struct {
+    proxy_balancer     *b;         /* balancer containing this worker */
+    proxy_worker       *w;
+    proxy_runtime_stat *s;
 } proxy_runtime_worker;
 
 struct proxy_balancer {
@@ -270,6 +276,11 @@ struct proxy_balancer {
     const char *sticky;          /* sticky session identifier */
     int         sticky_force;    /* Disable failover for sticky sessions */
     apr_interval_time_t timeout; /* Timeout for waiting on free connection */
+    /* XXX: Perhaps we will need the proc mutex too.
+     * Altrough we are only using arithmetic operations
+     * it may lead to a incorrect calculations.
+     * For now use only the thread mutex.
+     */
 #if APR_HAS_THREADS
     apr_thread_mutex_t  *mutex;  /* Thread lock for updating lb params */
 #endif
@@ -368,7 +379,7 @@ PROXY_DECLARE(proxy_worker *) ap_proxy_get_worker(apr_pool_t *p, proxy_server_co
 PROXY_DECLARE(const char *) ap_proxy_add_worker(proxy_worker **worker, apr_pool_t *p, proxy_server_conf *conf, const char *url);
 PROXY_DECLARE(struct proxy_balancer *) ap_proxy_get_balancer(apr_pool_t *p, proxy_server_conf *conf, const char *url);
 PROXY_DECLARE(const char *) ap_proxy_add_balancer(proxy_balancer **balancer, apr_pool_t *p, proxy_server_conf *conf, const char *url);
-PROXY_DECLARE(void) ap_proxy_add_worker_to_balancer(proxy_balancer *balancer, proxy_worker *worker);
+PROXY_DECLARE(void) ap_proxy_add_worker_to_balancer(apr_pool_t *pool, proxy_balancer *balancer, proxy_worker *worker);
 PROXY_DECLARE(int) ap_proxy_pre_request(proxy_worker **worker, proxy_balancer **balancer, request_rec *r, proxy_server_conf *conf, char **url);
 PROXY_DECLARE(int) ap_proxy_determine_connection(apr_pool_t *p, request_rec *r, proxy_server_conf *conf, proxy_worker *worker, proxy_conn_rec *conn,
                                                  apr_pool_t *ppool, apr_uri_t *uri, char **url, const char *proxyname, apr_port_t proxyport,
@@ -379,6 +390,16 @@ PROXY_DECLARE(apr_status_t) ap_proxy_close_connection(proxy_conn_rec *conn);
 PROXY_DECLARE(int) ap_proxy_connect_backend(const char *proxy_function, proxy_conn_rec *conn, proxy_worker *worker, server_rec *s);
 PROXY_DECLARE(int) ap_proxy_connection_create(const char *proxy_function, proxy_conn_rec *conn, conn_rec *c, server_rec *s);
 
+/* Scoreboard */
+#if MODULE_MAGIC_NUMBER_MAJOR > 20020903
+#define PROXY_HAS_SCOREBOARD 1
+#else
+#define PROXY_HAS_SCOREBOARD 0
+#endif
+/* The number of dynamic balancers that can be added */
+#define PROXY_DYNAMIC_BALANCER_LIMIT    16
+PROXY_DECLARE(int) ap_proxy_lb_workers(void);
+
 /* For proxy_util */
 extern module PROXY_DECLARE_DATA proxy_module;
 

diff --git a/modules/proxy/proxy_util.c b/modules/proxy/proxy_util.c
index f962512e776ce66a51cf64d7892f53390af8be77..f31ede2cf16c272f96102e8d09ad4c3652cca3f0 100644 (file)
--- a/modules/proxy/proxy_util.c
+++ b/modules/proxy/proxy_util.c
@@ -16,6 +16,7 @@
 /* Utility routines for Apache proxy */
 #include "mod_proxy.h"
 #include "ap_mpm.h"
+#include "scoreboard.h"
 #include "apr_version.h"
 
 #if (APR_MAJOR_VERSION < 1)
@@ -23,6 +24,9 @@
 #define apr_socket_create apr_socket_create_ex
 #endif
 
+/* Global balancer counter */
+static int lb_workers = 0;
+
 static int proxy_match_ipaddr(struct dirconn_entry *This, request_rec *r);
 static int proxy_match_domainname(struct dirconn_entry *This, request_rec *r);
 static int proxy_match_hostname(struct dirconn_entry *This, request_rec *r);
@@ -1038,7 +1042,7 @@ PROXY_DECLARE(const char *) ap_proxy_add_balancer(proxy_balancer **balancer,
             return "can not create thread mutex";
     }
 #endif
-    
+
     return NULL;
 }
 
@@ -1137,52 +1141,76 @@ PROXY_DECLARE(const char *) ap_proxy_add_worker(proxy_worker **worker,
 }
 
 PROXY_DECLARE(void) 
-ap_proxy_add_worker_to_balancer(proxy_balancer *balancer, proxy_worker *worker)
+ap_proxy_add_worker_to_balancer(apr_pool_t *pool, proxy_balancer *balancer, proxy_worker *worker)
 {
     int i;
     double median, ffactor = 0.0;
-    proxy_runtime_worker *runtime, *workers;
+    proxy_runtime_worker *runtime, *workers;    
+#if PROXY_HAS_SCOREBOARD
+    lb_score *score;
+#else
+    void *score;
+#endif
 
+#if PROXY_HAS_SCOREBOARD
+    int mpm_daemons;
+
+    ap_mpm_query(AP_MPMQ_HARD_LIMIT_DAEMONS, &mpm_daemons);
+    /* Check if we are prefork or single child */
+    if (worker->hmax && mpm_daemons > 1)
+        score = ap_get_scoreboard_lb(getpid(), lb_workers);
+    else
+#endif
+    {
+        /* Use the plain memory */
+        score = apr_pcalloc(pool, sizeof(proxy_runtime_stat));
+    }
+    if (!score)
+        return;
     runtime = apr_array_push(balancer->workers);
     runtime->w = worker;
+    runtime->s = (proxy_runtime_stat *)score;
+    runtime->s->id = lb_workers;
+    /* TODO: deal with the dynamic overflow */
+    ++lb_workers;
 
     /* Recalculate lbfactors */
     workers = (proxy_runtime_worker *)balancer->workers->elts;
 
     for (i = 0; i < balancer->workers->nelts; i++) {
         /* Set to the original configuration */
-        workers[i].lbfactor = workers[i].w->lbfactor;
-        ffactor += workers[i].lbfactor;
+        workers[i].s->lbfactor = workers[i].w->lbfactor;
+        ffactor += workers[i].s->lbfactor;
     }
     if (ffactor < 100.0) {
         int z = 0;
         for (i = 0; i < balancer->workers->nelts; i++) {
-            if (workers[i].lbfactor == 0.0) 
+            if (workers[i].s->lbfactor == 0.0) 
                 ++z;
         }
         if (z) {
             median = (100.0 - ffactor) / z;
             for (i = 0; i < balancer->workers->nelts; i++) {
-                if (workers[i].lbfactor == 0.0) 
-                    workers[i].lbfactor = median;
+                if (workers[i].s->lbfactor == 0.0) 
+                    workers[i].s->lbfactor = median;
             }
         }
         else {
             median = (100.0 - ffactor) / balancer->workers->nelts;
             for (i = 0; i < balancer->workers->nelts; i++)
-                workers[i].lbfactor += median;
+                workers[i].s->lbfactor += median;
         }
     }
     else if (ffactor > 100.0) {
         median = (ffactor - 100.0) / balancer->workers->nelts;
         for (i = 0; i < balancer->workers->nelts; i++) {
-            if (workers[i].lbfactor > median)
-                workers[i].lbfactor -= median;
+            if (workers[i].s->lbfactor > median)
+                workers[i].s->lbfactor -= median;
         }
     } 
     for (i = 0; i < balancer->workers->nelts; i++) {
         /* Update the status entires */
-        workers[i].lbstatus = workers[i].lbfactor;
+        workers[i].s->lbstatus = workers[i].s->lbfactor;
     }
 }
 
@@ -1757,3 +1785,8 @@ PROXY_DECLARE(int) ap_proxy_connection_create(const char *proxy_function,
 
     return OK;
 }
+
+PROXY_DECLARE(int) ap_proxy_lb_workers(void)
+{
+    return (lb_workers + PROXY_DYNAMIC_BALANCER_LIMIT);
+}