tcp: increase tcp_max_syn_backlog max value

[linux-2.6-microblaze.git] / Documentation / networking / ip-sysctl.txt

diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index 0e66534..8d4ad1d 100644 (file)
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -408,11 +408,14 @@ tcp_max_orphans - INTEGER
        up to ~64K of unswappable memory.
 
 tcp_max_syn_backlog - INTEGER
-       Maximal number of remembered connection requests, which have not
-       received an acknowledgment from connecting client.
+       Maximal number of remembered connection requests (SYN_RECV),
+       which have not received an acknowledgment from connecting client.
+       This is a per-listener limit.
        The minimal value is 128 for low memory machines, and it will
        increase in proportion to the memory of machine.
        If server suffers from overload, try increasing this number.
+       Remember to also check /proc/sys/net/core/somaxconn
+       A SYN_RECV request socket consumes about 304 bytes of memory.
 
 tcp_max_tw_buckets - INTEGER
        Maximal number of timewait sockets held by system simultaneously.