Add eviction-timeout option to allow graceful period for process restart on signals to be set separately.

4 files changed, 52 insertions, 7 deletions

diff --git a/docs/release-notes/version-4.4.7.rst b/docs/release-notes/version-4.4.7.rst
index a9b8de2..346cf5e 100644
--- a/docs/release-notes/version-4.4.7.rst
+++ b/docs/release-notes/version-4.4.7.rst
@@ -39,3 +39,21 @@ up proxying of a sub URL of the site to a remote URL.
 3. Added ``--proxy-virtual-host`` option to ``mod_wsgi-express`` for setting
 up proxying of a whole virtual host to a remote URL. Only supports proxying
 of HTTP requests and not HTTPS requests.
+
+4. Added ``eviction-timeout`` option to ``WSGIDaemonProcess`` directive.
+For the case where the graceful restart signal, usually ``SIGUSR1``, is
+sent to a daemon process to evict the WSGI application and restart the
+process, this controls how many seconds the process will wait, while still
+accepting new requests, before it reaches an idle state with no active
+requests and shuts down.
+
+The ``graceful-timeout`` option previously performed this exact role in
+this case previously, but a separate option is being added to allow a
+different timeout period to be specified for the case for forced eviction.
+The existing ``graceful-timeout`` option is still used when a maximum
+requests option or CPU usage limit is set. For backwards compatibility,
+if ``eviction-timeout`` isn't set, it will fall back to using any value
+specified using the ``graceful-timeout`` option.
+
+The ``--eviction-timeout`` option has also been added to
+``mod_wsgi-express`` and behaves in a similar fashion.
diff --git a/src/server/__init__.py b/src/server/__init__.py
index 0f4fc27..2bb59ec 100644
--- a/src/server/__init__.py
+++ b/src/server/__init__.py
@@ -267,6 +267,7 @@ WSGIDaemonProcess %(host)s:%(port)s \\
    inactivity-timeout=%(inactivity_timeout)s \\
    deadlock-timeout=%(deadlock_timeout)s \\
    graceful-timeout=%(graceful_timeout)s \\
+   eviction-timeout=%(eviction_timeout)s \\
    shutdown-timeout=%(shutdown_timeout)s \\
    send-buffer-size=%(send_buffer_size)s \\
    receive-buffer-size=%(receive_buffer_size)s \\
@@ -291,6 +292,7 @@ WSGIDaemonProcess %(host)s:%(port)s \\
    inactivity-timeout=%(inactivity_timeout)s \\
    deadlock-timeout=%(deadlock_timeout)s \\
    graceful-timeout=%(graceful_timeout)s \\
+   eviction-timeout=%(eviction_timeout)s \\
    shutdown-timeout=%(shutdown_timeout)s \\
    send-buffer-size=%(send_buffer_size)s \\
    receive-buffer-size=%(receive_buffer_size)s \\
@@ -1606,10 +1608,16 @@ option_list = (
 
     optparse.make_option('--graceful-timeout', type='int', default=15,
             metavar='SECONDS', help='Grace period for requests to complete '
-            'normally, without accepting new requests, when worker processes '
-            'are being shutdown and restarted due to maximum requests being '
-            'reached or due to graceful restart signal. Defaults to 15 '
-            'seconds.'),
+            'normally, while still accepting new requests, when worker '
+            'processes are being shutdown and restarted due to maximum '
+            'requests being reached. Defaults to 15 seconds.'),
+    optparse.make_option('--eviction-timeout', type='int', default=0,
+            metavar='SECONDS', help='Grace period for requests to complete '
+            'normally, while still accepting new requests, when the WSGI '
+            'application is being evicted from the worker processes, and '
+            'the process restarted, due to forced graceful restart signal. '
+            'Defaults to timeout specified by \'--graceful-timeout\' '
+            'option.'),
 
     optparse.make_option('--deadlock-timeout', type='int', default=60,
             metavar='SECONDS', help='Maximum number of seconds allowed '
diff --git a/src/server/mod_wsgi.c b/src/server/mod_wsgi.c
index f601cb8..30ddbe5 100644
--- a/src/server/mod_wsgi.c
+++ b/src/server/mod_wsgi.c
@@ -85,6 +85,7 @@ static apr_interval_time_t wsgi_deadlock_timeout = 0;
 static apr_interval_time_t wsgi_idle_timeout = 0;
 static apr_interval_time_t wsgi_request_timeout = 0;
 static apr_interval_time_t wsgi_graceful_timeout = 0;
+static apr_interval_time_t wsgi_eviction_timeout = 0;
 static apr_time_t volatile wsgi_deadlock_shutdown_time = 0;
 static apr_time_t volatile wsgi_idle_shutdown_time = 0;
 static apr_time_t volatile wsgi_graceful_shutdown_time = 0;
@@ -6596,6 +6597,7 @@ static const char *wsgi_add_daemon_process(cmd_parms *cmd, void *mconfig,
     int inactivity_timeout = 0;
     int request_timeout = 0;
     int graceful_timeout = 0;
+    int eviction_timeout = 0;
     int connect_timeout = 15;
     int socket_timeout = 0;
     int queue_timeout = 0;
@@ -6808,6 +6810,14 @@ static const char *wsgi_add_daemon_process(cmd_parms *cmd, void *mconfig,
             if (graceful_timeout < 0)
                 return "Invalid graceful timeout for WSGI daemon process.";
         }
+        else if (!strcmp(option, "eviction-timeout")) {
+            if (!*value)
+                return "Invalid eviction timeout for WSGI daemon process.";
+
+            eviction_timeout = atoi(value);
+            if (eviction_timeout < 0)
+                return "Invalid eviction timeout for WSGI daemon process.";
+        }
         else if (!strcmp(option, "connect-timeout")) {
             if (!*value)
                 return "Invalid connect timeout for WSGI daemon process.";
@@ -7077,6 +7087,7 @@ static const char *wsgi_add_daemon_process(cmd_parms *cmd, void *mconfig,
     entry->inactivity_timeout = apr_time_from_sec(inactivity_timeout);
     entry->request_timeout = apr_time_from_sec(request_timeout);
     entry->graceful_timeout = apr_time_from_sec(graceful_timeout);
+    entry->eviction_timeout = apr_time_from_sec(eviction_timeout);
     entry->connect_timeout = apr_time_from_sec(connect_timeout);
     entry->socket_timeout = apr_time_from_sec(socket_timeout);
     entry->queue_timeout = apr_time_from_sec(queue_timeout);
@@ -8288,6 +8299,9 @@ static void *wsgi_monitor_thread(apr_thread_t *thd, void *data)
         ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, wsgi_server,
                      "mod_wsgi (pid=%d): Graceful timeout is %d.",
                      getpid(), (int)(apr_time_sec(wsgi_graceful_timeout)));
+        ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, wsgi_server,
+                     "mod_wsgi (pid=%d): Eviction timeout is %d.",
+                     getpid(), (int)(apr_time_sec(wsgi_eviction_timeout)));
     }
 
     while (1) {
@@ -8579,6 +8593,7 @@ static void wsgi_daemon_main(apr_pool_t *p, WSGIDaemonProcess *daemon)
     wsgi_idle_timeout = daemon->group->inactivity_timeout;
     wsgi_request_timeout = daemon->group->request_timeout;
     wsgi_graceful_timeout = daemon->group->graceful_timeout;
+    wsgi_eviction_timeout = daemon->group->eviction_timeout;
 
     if (wsgi_deadlock_timeout || wsgi_idle_timeout) {
         rv = apr_thread_create(&reaper, thread_attr, wsgi_monitor_thread,
@@ -8751,17 +8766,20 @@ static void wsgi_daemon_main(apr_pool_t *p, WSGIDaemonProcess *daemon)
 
                     apr_thread_mutex_lock(wsgi_monitor_lock);
                     wsgi_graceful_shutdown_time = apr_time_now();
-                    wsgi_graceful_shutdown_time += wsgi_graceful_timeout;
+                    if (wsgi_eviction_timeout)
+                        wsgi_graceful_shutdown_time += wsgi_eviction_timeout;
+                    else
+                        wsgi_graceful_shutdown_time += wsgi_graceful_timeout;
                     apr_thread_mutex_unlock(wsgi_monitor_lock);
 
                     ap_log_error(APLOG_MARK, APLOG_INFO, 0, wsgi_server,
-                                 "mod_wsgi (pid=%d): Graceful shutdown "
+                                 "mod_wsgi (pid=%d): Process eviction "
                                  "requested, waiting for requests to complete "
                                  "'%s'.", getpid(), daemon->group->name);
                 }
                 else {
                     ap_log_error(APLOG_MARK, APLOG_INFO, 0, wsgi_server,
-                                 "mod_wsgi (pid=%d): Graceful shutdown "
+                                 "mod_wsgi (pid=%d): Process eviction "
                                  "requested, triggering immediate shutdown "
                                  "'%s'.", getpid(), daemon->group->name);
 
diff --git a/src/server/wsgi_daemon.h b/src/server/wsgi_daemon.h
index c6ba8a9..999fca2 100644
--- a/src/server/wsgi_daemon.h
+++ b/src/server/wsgi_daemon.h
@@ -113,6 +113,7 @@ typedef struct {
     apr_time_t inactivity_timeout;
     apr_time_t request_timeout;
     apr_time_t graceful_timeout;
+    apr_time_t eviction_timeout;
     apr_time_t connect_timeout;
     apr_time_t socket_timeout;
     apr_time_t queue_timeout;