MEDIUM: peers: Balance applets across threads
When creating a new applet for peer outgoing connection, we check
the load on each thread. Threads with least applet count are
preferred.
With this solution we avoid a situation when many outgoing
connections run on the same thread causing significant load on
single CPU core.
diff --git a/src/peers.c b/src/peers.c
index d46afcf..6f71ded 100644
--- a/src/peers.c
+++ b/src/peers.c
@@ -3196,7 +3196,8 @@
static struct appctx *peer_session_create(struct peers *peers, struct peer *peer)
{
struct appctx *appctx;
- unsigned int thr = tid;
+ unsigned int thr = 0;
+ int idx;
peer->new_conn++;
peer->reconnect = tick_add(now_ms, MS_TO_TICKS(PEER_RECONNECT_TIMEOUT));
@@ -3204,7 +3205,9 @@
peer->statuscode = PEER_SESS_SC_CONNECTCODE;
peer->last_hdshk = now_ms;
- appctx = appctx_new_here(&peer_applet, NULL);
+ for (idx = 0; idx < global.nbthread; idx++)
+ thr = peers->applet_count[idx] < peers->applet_count[thr] ? idx : thr;
+ appctx = appctx_new_on(&peer_applet, NULL, thr);
if (!appctx)
goto out_close;
appctx->svcctx = (void *)peer;
@@ -3212,10 +3215,8 @@
appctx->st0 = PEER_SESS_ST_CONNECT;
peer->appctx = appctx;
- if (appctx_init(appctx) == -1)
- goto out_free_appctx;
-
HA_ATOMIC_INC(&peers->applet_count[thr]);
+ appctx_wakeup(appctx);
return appctx;
/* Error unrolling */