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From: Eliezer Tamir <>
To: Micahel Kerrisk <>
Cc:, David Miller <>,,,
	Andrew Morton <>,
	Eliezer Tamir <>
Subject: [PATCH v2] socket.7: add description for SO_BUSY_POLL
Date: Wed, 10 Jul 2013 17:18:35 +0300	[thread overview]
Message-ID: <> (raw)

Add description for the SO_BUSY_POLL socket option to the socket(7) manpage.

fixed typos reported by Rasmus Villemoes

Signed-off-by: Eliezer Tamir <>

 man7/socket.7 |   25 +++++++++++++++++++++++++
 1 files changed, 25 insertions(+), 0 deletions(-)

diff --git a/man7/socket.7 b/man7/socket.7
index f2213eb..5edcb09 100644
--- a/man7/socket.7
+++ b/man7/socket.7
@@ -694,6 +694,31 @@ for details on control messages.
 Gets the socket type as an integer (e.g.,
 This socket option is read-only.
+Sets the approximate time in microseconds to busy poll on a blocking receive
+when there is no data. Increasing this value requires
+The default for this option is controlled by the
+.I /proc/sys/net/core/busy_read
+The value in the  
+.I /proc/sys/net/core/busy_poll
+file determines how long 
+.BR select (2)
+.BR poll (2)
+will busy poll when they operate on sockets with 
+set and no events to report are found.
+In both cases busy polling will only be done when the socket last received data
+from a network device that supports this option.
+While busy polling may improve latency of some applications, care must be
+taken when using it since this will increase both CPU utilization and power usage.
 .SS Signals
 When writing onto a connection-oriented socket that has been shut down
 (by the local or the remote end)

             reply	other threads:[~2013-07-10 14:18 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-07-10 14:18 Eliezer Tamir [this message]
2013-07-10 18:03 ` [PATCH v2] socket.7: add description for SO_BUSY_POLL Michael Kerrisk
2013-07-10 18:52   ` David Miller
2013-07-10 18:57     ` Michael Kerrisk (man-pages)
2013-07-10 19:01       ` David Miller
2013-07-10 18:56   ` Eliezer Tamir
2014-01-20 16:28 ` Michael Kerrisk (man-pages)
2014-01-20 17:28   ` Eliezer Tamir
2015-02-05 13:17     ` Michael Kerrisk (man-pages)
2015-02-05 17:48       ` Eliezer Tamir

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