Hi all,
this patch has been sitting in my local repository for quite some time
now. The number of backlog connections helps diagnosing realserver related
overload and configuration problems. Is it worth merging? If yes, I'm
going to tidy it up and prepare the userspace portion for ipvsadm.
Sven
From: Sven Wegener <sven.wegener@xxxxxxxxxxx>
Subject: [PATCH] ipvs: Keep track of backlog connections
A backlog connection is a connection that is on its way from inactive to
active. Speaking in TCP language, a connection from which we've seen the
initial SYN packet, but the three-way handshake hasn't finished yet.
These connections are expected to move to active soon. When a
destination is overloaded or isn't able to successfully establish
connections for various reasons, this count increases quickly and is an
indication for a problem.
Signed-off-by: Sven Wegener <sven.wegener@xxxxxxxxxxx>
---
include/linux/ip_vs.h | 3 +++
include/net/ip_vs.h | 1 +
net/netfilter/ipvs/ip_vs_conn.c | 3 +++
net/netfilter/ipvs/ip_vs_ctl.c | 3 +++
net/netfilter/ipvs/ip_vs_proto_tcp.c | 10 ++++++++++
net/netfilter/ipvs/ip_vs_sync.c | 4 ++--
6 files changed, 22 insertions(+), 2 deletions(-)
diff --git a/include/linux/ip_vs.h b/include/linux/ip_vs.h
index 9708de2..4fe6565 100644
--- a/include/linux/ip_vs.h
+++ b/include/linux/ip_vs.h
@@ -87,6 +87,7 @@
#define IP_VS_CONN_F_NO_CPORT 0x0800 /* no client port set yet */
#define IP_VS_CONN_F_TEMPLATE 0x1000 /* template, not connection */
#define IP_VS_CONN_F_ONE_PACKET 0x2000 /* forward only one
packet */
+#define IP_VS_CONN_F_BACKLOG 0x4000 /* backlog connection */
#define IP_VS_SCHEDNAME_MAXLEN 16
#define IP_VS_IFNAME_MAXLEN 16
@@ -350,6 +351,8 @@ enum {
IPVS_DEST_ATTR_PERSIST_CONNS, /* persistent connections */
IPVS_DEST_ATTR_STATS, /* nested attribute for dest stats */
+
+ IPVS_DEST_ATTR_BACKLOG_CONNS, /* backlog connections */
__IPVS_DEST_ATTR_MAX,
};
diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h
index a4747a0..c39dee6 100644
--- a/include/net/ip_vs.h
+++ b/include/net/ip_vs.h
@@ -499,6 +499,7 @@ struct ip_vs_dest {
/* connection counters and thresholds */
atomic_t activeconns; /* active connections */
atomic_t inactconns; /* inactive connections */
+ atomic_t backlogconns; /* backlog connections */
atomic_t persistconns; /* persistent connections */
__u32 u_threshold; /* upper threshold */
__u32 l_threshold; /* lower threshold */
diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c
index b71c69a..486dd48 100644
--- a/net/netfilter/ipvs/ip_vs_conn.c
+++ b/net/netfilter/ipvs/ip_vs_conn.c
@@ -607,6 +607,9 @@ static inline void ip_vs_unbind_dest(struct ip_vs_conn *cp)
} else {
atomic_dec(&dest->activeconns);
}
+
+ if (cp->flags & IP_VS_CONN_F_BACKLOG)
+ atomic_dec(&dest->backlogconns);
} else {
/* It is a persistent connection/template, so decrease
the peristent connection counter */
diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c
index 0f0c079..1933e60 100644
--- a/net/netfilter/ipvs/ip_vs_ctl.c
+++ b/net/netfilter/ipvs/ip_vs_ctl.c
@@ -2579,6 +2579,7 @@ static const struct nla_policy
ip_vs_dest_policy[IPVS_DEST_ATTR_MAX + 1] = {
[IPVS_DEST_ATTR_INACT_CONNS] = { .type = NLA_U32 },
[IPVS_DEST_ATTR_PERSIST_CONNS] = { .type = NLA_U32 },
[IPVS_DEST_ATTR_STATS] = { .type = NLA_NESTED },
+ [IPVS_DEST_ATTR_BACKLOG_CONNS] = { .type = NLA_U32 },
};
static int ip_vs_genl_fill_stats(struct sk_buff *skb, int container_type,
@@ -2826,6 +2827,8 @@ static int ip_vs_genl_fill_dest(struct sk_buff *skb,
struct ip_vs_dest *dest)
atomic_read(&dest->activeconns));
NLA_PUT_U32(skb, IPVS_DEST_ATTR_INACT_CONNS,
atomic_read(&dest->inactconns));
+ NLA_PUT_U32(skb, IPVS_DEST_ATTR_BACKLOG_CONNS,
+ atomic_read(&dest->backlogconns));
NLA_PUT_U32(skb, IPVS_DEST_ATTR_PERSIST_CONNS,
atomic_read(&dest->persistconns));
diff --git a/net/netfilter/ipvs/ip_vs_proto_tcp.c
b/net/netfilter/ipvs/ip_vs_proto_tcp.c
index 282d24d..c92cbab 100644
--- a/net/netfilter/ipvs/ip_vs_proto_tcp.c
+++ b/net/netfilter/ipvs/ip_vs_proto_tcp.c
@@ -510,6 +510,16 @@ set_tcp_state(struct ip_vs_protocol *pp, struct ip_vs_conn
*cp,
atomic_dec(&dest->inactconns);
cp->flags &= ~IP_VS_CONN_F_INACTIVE;
}
+
+ if (new_state == IP_VS_TCP_S_SYN_RECV &&
+ !(cp->flags & IP_VS_CONN_F_BACKLOG)) {
+ atomic_inc(&dest->backlogconns);
+ cp->flags |= IP_VS_CONN_F_BACKLOG;
+ } else if (new_state == IP_VS_TCP_S_ESTABLISHED &&
+ cp->flags & IP_VS_CONN_F_BACKLOG) {
+ atomic_dec(&dest->backlogconns);
+ cp->flags &= ~IP_VS_CONN_F_BACKLOG;
+ }
}
}
diff --git a/net/netfilter/ipvs/ip_vs_sync.c b/net/netfilter/ipvs/ip_vs_sync.c
index 7ba0693..ceb1cd9 100644
--- a/net/netfilter/ipvs/ip_vs_sync.c
+++ b/net/netfilter/ipvs/ip_vs_sync.c
@@ -264,7 +264,7 @@ void ip_vs_sync_conn(struct ip_vs_conn *cp)
s->caddr = cp->caddr.ip;
s->vaddr = cp->vaddr.ip;
s->daddr = cp->daddr.ip;
- s->flags = htons(cp->flags & ~IP_VS_CONN_F_HASHED);
+ s->flags = htons(cp->flags & ~(IP_VS_CONN_F_HASHED |
IP_VS_CONN_F_BACKLOG));
s->state = htons(cp->state);
if (cp->flags & IP_VS_CONN_F_SEQ_MASK) {
struct ip_vs_sync_conn_options *opt =
@@ -334,7 +334,7 @@ static void ip_vs_process_message(const char *buffer, const
size_t buflen)
}
s = (struct ip_vs_sync_conn *) p;
flags = ntohs(s->flags) | IP_VS_CONN_F_SYNC;
- flags &= ~IP_VS_CONN_F_HASHED;
+ flags &= ~(IP_VS_CONN_F_HASHED | IP_VS_CONN_F_BACKLOG);
if (flags & IP_VS_CONN_F_SEQ_MASK) {
opt = (struct ip_vs_sync_conn_options *)&s[1];
p += FULL_CONN_SIZE;
--
To unsubscribe from this list: send the line "unsubscribe lvs-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
|