diff options
| -rw-r--r-- | Documentation/networking/bonding.txt | 7 | ||||
| -rw-r--r-- | Documentation/networking/ip-sysctl.txt | 10 | ||||
| -rw-r--r-- | include/linux/tcp.h | 4 | ||||
| -rw-r--r-- | include/net/tcp.h | 4 | ||||
| -rw-r--r-- | net/ipv4/sysctl_net_ipv4.c | 7 | ||||
| -rw-r--r-- | net/ipv4/tcp_input.c | 3 |
6 files changed, 23 insertions, 12 deletions
diff --git a/Documentation/networking/bonding.txt b/Documentation/networking/bonding.txt index eeb5b2e97bed..83bf4986baea 100644 --- a/Documentation/networking/bonding.txt +++ b/Documentation/networking/bonding.txt @@ -2230,11 +2230,8 @@ balance-rr: This mode is the only mode that will permit a single It is possible to adjust TCP/IP's congestion limits by altering the net.ipv4.tcp_reordering sysctl parameter. The - usual default value is 3, and the maximum useful value is 127. - For a four interface balance-rr bond, expect that a single - TCP/IP stream will utilize no more than approximately 2.3 - interface's worth of throughput, even after adjusting - tcp_reordering. + usual default value is 3. But keep in mind TCP stack is able + to automatically increase this when it detects reorders. Note that the fraction of packets that will be delivered out of order is highly variable, and is unlikely to be zero. The level diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index 0307e2875f21..9028b879a97b 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -376,9 +376,17 @@ tcp_orphan_retries - INTEGER may consume significant resources. Cf. tcp_max_orphans. tcp_reordering - INTEGER - Maximal reordering of packets in a TCP stream. + Initial reordering level of packets in a TCP stream. + TCP stack can then dynamically adjust flow reordering level + between this initial value and tcp_max_reordering Default: 3 +tcp_max_reordering - INTEGER + Maximal reordering level of packets in a TCP stream. + 300 is a fairly conservative value, but you might increase it + if paths are using per packet load balancing (like bonding rr mode) + Default: 300 + tcp_retrans_collapse - BOOLEAN Bug-to-bug compatibility with some broken printers. On retransmit try to send bigger packets to work around bugs in diff --git a/include/linux/tcp.h b/include/linux/tcp.h index c2dee7deefa8..f566b8567892 100644 --- a/include/linux/tcp.h +++ b/include/linux/tcp.h @@ -204,10 +204,10 @@ struct tcp_sock { u16 urg_data; /* Saved octet of OOB data and control flags */ u8 ecn_flags; /* ECN status bits. */ - u8 reordering; /* Packet reordering metric. */ + u8 keepalive_probes; /* num of allowed keep alive probes */ + u32 reordering; /* Packet reordering metric. */ u32 snd_up; /* Urgent pointer */ - u8 keepalive_probes; /* num of allowed keep alive probes */ /* * Options received (usually on last packet, some only on SYN packets). */ diff --git a/include/net/tcp.h b/include/net/tcp.h index c73fc145ee45..3a35b1500359 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -70,9 +70,6 @@ void tcp_time_wait(struct sock *sk, int state, int timeo); /* After receiving this amount of duplicate ACKs fast retransmit starts. */ #define TCP_FASTRETRANS_THRESH 3 -/* Maximal reordering. */ -#define TCP_MAX_REORDERING 127 - /* Maximal number of ACKs sent quickly to accelerate slow-start. */ #define TCP_MAX_QUICKACKS 16U @@ -252,6 +249,7 @@ extern int sysctl_tcp_abort_on_overflow; extern int sysctl_tcp_max_orphans; extern int sysctl_tcp_fack; extern int sysctl_tcp_reordering; +extern int sysctl_tcp_max_reordering; extern int sysctl_tcp_dsack; extern long sysctl_tcp_mem[3]; extern int sysctl_tcp_wmem[3]; diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c index b3c53c8b331e..e0ee384a448f 100644 --- a/net/ipv4/sysctl_net_ipv4.c +++ b/net/ipv4/sysctl_net_ipv4.c @@ -496,6 +496,13 @@ static struct ctl_table ipv4_table[] = { .proc_handler = proc_dointvec }, { + .procname = "tcp_max_reordering", + .data = &sysctl_tcp_max_reordering, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, + { .procname = "tcp_dsack", .data = &sysctl_tcp_dsack, .maxlen = sizeof(int), diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index a12b455928e5..9a18cdd633f3 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -81,6 +81,7 @@ int sysctl_tcp_window_scaling __read_mostly = 1; int sysctl_tcp_sack __read_mostly = 1; int sysctl_tcp_fack __read_mostly = 1; int sysctl_tcp_reordering __read_mostly = TCP_FASTRETRANS_THRESH; +int sysctl_tcp_max_reordering __read_mostly = 300; EXPORT_SYMBOL(sysctl_tcp_reordering); int sysctl_tcp_dsack __read_mostly = 1; int sysctl_tcp_app_win __read_mostly = 31; @@ -833,7 +834,7 @@ static void tcp_update_reordering(struct sock *sk, const int metric, if (metric > tp->reordering) { int mib_idx; - tp->reordering = min(TCP_MAX_REORDERING, metric); + tp->reordering = min(sysctl_tcp_max_reordering, metric); /* This exciting event is worth to be remembered. 8) */ if (ts) |