[OPTIM] introduce global parameter "tune.maxaccept"

This new parameter makes it possible to override the default
number of consecutive incoming connections which can be
accepted on a socket. By default it is not limited on single
process mode, and limited to 8 in multi-process mode.

diff --git a/doc/configuration.txt b/doc/configuration.txt
index 1c7a058d24f9e5cb269870bd6837a8fc3d94e37e..ea3d342c20a40542203862d3c150dc9022aff257 100644 (file)
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -67,8 +67,9 @@ The following keywords are supported in the "global" section :
    - nokqueue
    - nopoll
    - nosepoll
-   - tune.maxpollevents
    - spread-checks
+   - tune.maxaccept
+   - tune.maxpollevents
   
  * Debugging
    - debug
@@ -212,13 +213,6 @@ nosepoll
   is equivalent to the command-line argument "-ds". The next polling system
   used will generally be "epoll". See also "nosepoll", and "nopoll".
 
-tune.maxpollevents <number>
-  Sets the maximum amount of events that can be processed at once in a call to
-  the polling system. The default value is adapted to the operating system. It
-  has been noticed that reducing it below 200 tends to slightly decrease
-  latency at the expense of network bandwidth, and increasing it above 200
-  tends to trade latency for slightly increased bandwidth.
-
 spread-checks <0..50, in percent>
   Sometimes it is desirable to avoid sending health checks to servers at exact
   intervals, for instance when many logical servers are located on the same
@@ -226,6 +220,23 @@ spread-checks <0..50, in percent>
   some randomness in the check interval between 0 and +/- 50%. A value between
   2 and 5 seems to show good results. The default value remains at 0.
 
+tune.maxaccept <number>
+  Sets the maximum number of consecutive accepts that a process may perform on
+  a single wake up. High values give higher priority to high connection rates,
+  while lower values give higher priority to already established connections.
+  This value is unlimited by default in single process mode. However, in
+  multi-process mode (nbproc > 1), it defaults to 8 so that when one process
+  wakes up, it does not take all incoming connections for itself and leaves a
+  part of them to other processes. Setting this value to zero or less disables
+  the limitation. It should normally not be needed to tweak this value.
+
+tune.maxpollevents <number>
+  Sets the maximum amount of events that can be processed at once in a call to
+  the polling system. The default value is adapted to the operating system. It
+  has been noticed that reducing it below 200 tends to slightly decrease
+  latency at the expense of network bandwidth, and increasing it above 200
+  tends to trade latency for slightly increased bandwidth.
+
 
 1.3) Debugging
 ---------------

diff --git a/include/types/global.h b/include/types/global.h
index 18a94b291f4cf2ce60f620ff4197758767af801c..16369540b11e7d01d23dbff4e9a2a9f28048ff1d 100644 (file)
--- a/include/types/global.h
+++ b/include/types/global.h
@@ -63,6 +63,7 @@ struct global {
        struct logsrv logsrv1, logsrv2;
        struct {
                int maxpollevents; /* max number of poll events at once */
+               int maxaccept;     /* max number of consecutive accept() */
        } tune;
        struct listener stats_sock; /* unix socket listener for statistics */
        struct timeval stats_timeout;

diff --git a/src/cfgparse.c b/src/cfgparse.c
index 7b43b7e68d4e346338a7d45c501bc2af72558c79..655a40e63442d79b4886193ba2a0d9177e9e7e63 100644 (file)
--- a/src/cfgparse.c
+++ b/src/cfgparse.c
@@ -307,6 +307,17 @@ int cfg_parse_global(const char *file, int linenum, char **args, int inv)
                }
                global.tune.maxpollevents = atol(args[1]);
        }
+       else if (!strcmp(args[0], "tune.maxaccept")) {
+               if (global.tune.maxaccept != 0) {
+                       Alert("parsing [%s:%d] : '%s' already specified. Continuing.\n", file, linenum, args[0]);
+                       return 0;
+               }
+               if (*(args[1]) == 0) {
+                       Alert("parsing [%s:%d] : '%s' expects an integer argument.\n", file, linenum, args[0]);
+                       return -1;
+               }
+               global.tune.maxaccept = atol(args[1]);
+       }
        else if (!strcmp(args[0], "uid")) {
                if (global.uid != 0) {
                        Alert("parsing [%s:%d] : user/uid already specified. Continuing.\n", file, linenum);

diff --git a/src/client.c b/src/client.c
index 2505db305613020042cad5178371b61e61dc55b9..cfcfb0c3f8d9cb08c07311c684c3b56b3dda2f4e 100644 (file)
--- a/src/client.c
+++ b/src/client.c
@@ -74,12 +74,7 @@ int event_accept(int fd) {
        struct http_txn *txn;
        struct task *t;
        int cfd;
-       int max_accept;
-
-       if (global.nbproc > 1)
-               max_accept = 8; /* let other processes catch some connections too */
-       else
-               max_accept = -1;
+       int max_accept = global.tune.maxaccept;
 
        while (p->feconn < p->maxconn && max_accept--) {
                struct sockaddr_storage addr;

diff --git a/src/haproxy.c b/src/haproxy.c
index fd7c96e6ea14394db50b1e4a7fb028dbce50fa6d..f4f7b17a77589a7b255a8910bd62cb8c452de48a 100644 (file)
--- a/src/haproxy.c
+++ b/src/haproxy.c
@@ -569,6 +569,13 @@ void init(int argc, char **argv)
        if (global.tune.maxpollevents <= 0)
                global.tune.maxpollevents = MAX_POLL_EVENTS;
 
+       if (global.tune.maxaccept <= 0) {
+               if (global.nbproc > 1)
+                       global.tune.maxaccept = 8;  /* leave some conns to other processes */
+               else
+                       global.tune.maxaccept = -1; /* accept all incoming conns */
+       }
+
        if (arg_mode & (MODE_DEBUG | MODE_FOREGROUND)) {
                /* command line debug mode inhibits configuration mode */
                global.mode &= ~(MODE_DAEMON | MODE_QUIET);