From efac52762b1e3fe3035d29e82d8ee1aebc45e4a7 Mon Sep 17 00:00:00 2001 From: "Rumen G. Bogdanovski" Date: Wed, 7 Nov 2007 02:36:55 -0800 Subject: [PATCH] [IPVS]: Synchronize closing of Connections This patch makes the master daemon to sync the connection when it is about to close. This makes the connections on the backup to close or timeout according their state. Before the sync was performed only if the connection is in ESTABLISHED state which always made the connections to timeout in the hard coded 3 minutes. However the Andy Gospodarek's patch ([IPVS]: use proper timeout instead of fixed value) effectively did nothing more than increasing this to 15 minutes (Established state timeout). So this patch makes use of proper timeout since it syncs the connections on status changes to FIN_WAIT (2min timeout) and CLOSE (10sec timeout). However if the backup misses CLOSE hopefully it did not miss FIN_WAIT. Otherwise we will just have to wait for the ESTABLISHED state timeout. As it is without this patch. This way the number of the hanging connections on the backup is kept to minimum. And very few of them will be left to timeout with a long timeout. This is important if we want to make use of the fix for the real server overcommit on master/backup fail-over. Signed-off-by: Rumen G. Bogdanovski Signed-off-by: Simon Horman Signed-off-by: David S. Miller --- include/net/ip_vs.h | 4 ++++ net/ipv4/ipvs/ip_vs_core.c | 20 ++++++++++++++------ net/ipv4/ipvs/ip_vs_sync.c | 2 +- 3 files changed, 19 insertions(+), 7 deletions(-) diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h index 1fd1ee896f..67ea2c0c0a 100644 --- a/include/net/ip_vs.h +++ b/include/net/ip_vs.h @@ -520,6 +520,10 @@ struct ip_vs_conn { spinlock_t lock; /* lock for state transition */ volatile __u16 flags; /* status flags */ volatile __u16 state; /* state info */ + volatile __u16 old_state; /* old state, to be used for + * state transition triggerd + * synchronization + */ /* Control members */ struct ip_vs_conn *control; /* Master control connection */ diff --git a/net/ipv4/ipvs/ip_vs_core.c b/net/ipv4/ipvs/ip_vs_core.c index c6ed7654e8..20c884a577 100644 --- a/net/ipv4/ipvs/ip_vs_core.c +++ b/net/ipv4/ipvs/ip_vs_core.c @@ -979,15 +979,23 @@ ip_vs_in(unsigned int hooknum, struct sk_buff *skb, ret = NF_ACCEPT; } - /* increase its packet counter and check if it is needed - to be synchronized */ + /* Increase its packet counter and check if it is needed + * to be synchronized + * + * Sync connection if it is about to close to + * encorage the standby servers to update the connections timeout + */ atomic_inc(&cp->in_pkts); if ((ip_vs_sync_state & IP_VS_STATE_MASTER) && - (cp->protocol != IPPROTO_TCP || - cp->state == IP_VS_TCP_S_ESTABLISHED) && - (atomic_read(&cp->in_pkts) % sysctl_ip_vs_sync_threshold[1] - == sysctl_ip_vs_sync_threshold[0])) + (((cp->protocol != IPPROTO_TCP || + cp->state == IP_VS_TCP_S_ESTABLISHED) && + (atomic_read(&cp->in_pkts) % sysctl_ip_vs_sync_threshold[1] + == sysctl_ip_vs_sync_threshold[0])) || + ((cp->protocol == IPPROTO_TCP) && (cp->old_state != cp->state) && + ((cp->state == IP_VS_TCP_S_FIN_WAIT) || + (cp->state == IP_VS_TCP_S_CLOSE))))) ip_vs_sync_conn(cp); + cp->old_state = cp->state; ip_vs_conn_put(cp); return ret; diff --git a/net/ipv4/ipvs/ip_vs_sync.c b/net/ipv4/ipvs/ip_vs_sync.c index b1694d67ab..bd930efc18 100644 --- a/net/ipv4/ipvs/ip_vs_sync.c +++ b/net/ipv4/ipvs/ip_vs_sync.c @@ -343,7 +343,6 @@ static void ip_vs_process_message(const char *buffer, const size_t buflen) if (!dest) { /* it is an unbound entry created by * synchronization */ - cp->state = ntohs(s->state); cp->flags = flags | IP_VS_CONN_F_HASHED; } else atomic_dec(&dest->refcnt); @@ -358,6 +357,7 @@ static void ip_vs_process_message(const char *buffer, const size_t buflen) p += SIMPLE_CONN_SIZE; atomic_set(&cp->in_pkts, sysctl_ip_vs_sync_threshold[0]); + cp->state = ntohs(s->state); pp = ip_vs_proto_get(s->protocol); cp->timeout = pp->timeout_table[cp->state]; ip_vs_conn_put(cp); -- 2.39.5