diff options
Diffstat (limited to 'Documentation/sysctl/net.txt')
| -rw-r--r-- | Documentation/sysctl/net.txt | 81 |
1 files changed, 75 insertions, 6 deletions
diff --git a/Documentation/sysctl/net.txt b/Documentation/sysctl/net.txt index cbd05ffc606..9a0319a8247 100644 --- a/Documentation/sysctl/net.txt +++ b/Documentation/sysctl/net.txt @@ -1,4 +1,4 @@ -Documentation for /proc/sys/net/* kernel version 2.4.0-test11-pre4 +Documentation for /proc/sys/net/* (c) 1999 Terrehon Bowden <terrehon@pacbell.net> Bodo Bauer <bb@ricochet.net> (c) 2000 Jorge Nerin <comandante@zaralinux.com> @@ -9,10 +9,10 @@ For general info and legal blurb, please look in README. ============================================================== This file contains the documentation for the sysctl files in -/proc/sys/net and is valid for Linux kernel version 2.4.0-test11-pre4. +/proc/sys/net The interface to the networking parts of the kernel is located in -/proc/sys/net. The following table shows all possible subdirectories.You may +/proc/sys/net. The following table shows all possible subdirectories. You may see only some of them, depending on your kernel's configuration. @@ -26,12 +26,67 @@ Table : Subdirectories in /proc/sys/net ipv4 IP version 4 x25 X.25 protocol ipx IPX token-ring IBM token ring bridge Bridging decnet DEC net - ipv6 IP version 6 + ipv6 IP version 6 tipc TIPC .............................................................................. 1. /proc/sys/net/core - Network core options ------------------------------------------------------- +bpf_jit_enable +-------------- + +This enables Berkeley Packet Filter Just in Time compiler. +Currently supported on x86_64 architecture, bpf_jit provides a framework +to speed packet filtering, the one used by tcpdump/libpcap for example. +Values : + 0 - disable the JIT (default value) + 1 - enable the JIT + 2 - enable the JIT and ask the compiler to emit traces on kernel log. + +dev_weight +-------------- + +The maximum number of packets that kernel can handle on a NAPI interrupt, +it's a Per-CPU variable. +Default: 64 + +default_qdisc +-------------- + +The default queuing discipline to use for network devices. This allows +overriding the default queue discipline of pfifo_fast with an +alternative. Since the default queuing discipline is created with the +no additional parameters so is best suited to queuing disciplines that +work well without configuration like stochastic fair queue (sfq), +CoDel (codel) or fair queue CoDel (fq_codel). Don't use queuing disciplines +like Hierarchical Token Bucket or Deficit Round Robin which require setting +up classes and bandwidths. +Default: pfifo_fast + +busy_read +---------------- +Low latency busy poll timeout for socket reads. (needs CONFIG_NET_RX_BUSY_POLL) +Approximate time in us to busy loop waiting for packets on the device queue. +This sets the default value of the SO_BUSY_POLL socket option. +Can be set or overridden per socket by setting socket option SO_BUSY_POLL, +which is the preferred method of enabling. If you need to enable the feature +globally via sysctl, a value of 50 is recommended. +Will increase power usage. +Default: 0 (off) + +busy_poll +---------------- +Low latency busy poll timeout for poll and select. (needs CONFIG_NET_RX_BUSY_POLL) +Approximate time in us to busy loop waiting for events. +Recommended value depends on the number of sockets you poll on. +For several sockets 50, for several hundreds 100. +For more than that you probably want to use epoll. +Note that only sockets with SO_BUSY_POLL set will be busy polled, +so you want to either selectively set SO_BUSY_POLL on those sockets or set +sysctl.net.busy_read globally. +Will increase power usage. +Default: 0 (off) + rmem_default ------------ @@ -75,8 +130,7 @@ netdev_budget Maximum number of packets taken from all interfaces in one polling cycle (NAPI poll). In one polling cycle interfaces which are registered to polling are -probed in a round-robin manner. The limit of packets in one such probe can be -set per-device via sysfs class/net/<device>/weight . +probed in a round-robin manner. netdev_max_backlog ------------------ @@ -183,3 +237,18 @@ IPX. The /proc/net/ipx_route table holds a list of IPX routes. For each route it gives the destination network, the router node (or Directly) and the network address of the router (or Connected) for internal networks. + +6. TIPC +------------------------------------------------------- + +The TIPC protocol now has a tunable for the receive memory, similar to the +tcp_rmem - i.e. a vector of 3 INTEGERs: (min, default, max) + + # cat /proc/sys/net/tipc/tipc_rmem + 4252725 34021800 68043600 + # + +The max value is set to CONN_OVERLOAD_LIMIT, and the default and min values +are scaled (shifted) versions of that same value. Note that the min value +is not at this point in time used in any meaningful way, but the triplet is +preserved in order to be consistent with things like tcp_rmem. |