This reverts commit 92cfe3260e.
Kernel commit 3f95f55eb55d ("net: sched: pie: change tc_pie_xstats->prob")
removes the need to change the maximum integer value of
tc_pie_stats->prob here.
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Leslie Monis <lesliemonis@gmail.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Kernel commit 105e808c1da2 ("pie: remove pie_vars->accu_prob_overflows"),
changes the maximum value of tc_pie_xstats->prob from (2^64 - 1) to
(2^56 - 1).
Signed-off-by: Mohit P. Tahiliani <tahiliani@nitk.edu.in>
Signed-off-by: Gautam Ramakrishnan <gautamramk@gmail.com>
Signed-off-by: Leslie Monis <lesliemonis@gmail.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Enable proper JSON output for the PIE Qdisc.
Use sprint_time() to print the value of tc_pie_xstats->delay.
Use the long double format specifier to print tc_pie_xstats->prob.
Also, fix the indentation in the oneline output of statistics and update
the man page to reflect this change.
Signed-off-by: Leslie Monis <lesliemonis@gmail.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Warning was:
q_pie.c:202:22: error: implicit conversion from 'unsigned long' to
'double'
Fixes: 492ec9558b ("tc: pie: change maximum integer value of tc_pie_xstats->prob")
Cc: Leslie Monis <lesliemonis@gmail.com>
Signed-off-by: Brian Vazquez <brianvv@google.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
PIE now uses per packet timestamps to calculate queuing
delay. The average dequeue rate based queue delay
calculation is now made optional. This patch adds the option
to enable or disable the use of Little's law to calculate
queuing delay.
Signed-off-by: Gautam Ramakrishnan <gautamramk@gmail.com>
Signed-off-by: Leslie Monis <lesliemonis@gmail.com>
Signed-off-by: Mohit P. Tahiliani <tahiliani@nitk.edu.in>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Every tool in the iproute2 package have one or more function to show
an help message to the user. Some of these functions print the help
line by line with a series of printf call, e.g. ip/xfrm_state.c does
60 fprintf calls.
If we group all the calls to a single one and just concatenate strings,
we save a lot of libc calls and thus object size. The size difference
of the compiled binaries calculated with bloat-o-meter is:
ip/ip:
add/remove: 0/0 grow/shrink: 5/15 up/down: 103/-4796 (-4693)
Total: Before=672591, After=667898, chg -0.70%
ip/rtmon:
add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-54 (-54)
Total: Before=48879, After=48825, chg -0.11%
tc/tc:
add/remove: 0/2 grow/shrink: 31/10 up/down: 882/-6133 (-5251)
Total: Before=351912, After=346661, chg -1.49%
bridge/bridge:
add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-459 (-459)
Total: Before=70502, After=70043, chg -0.65%
misc/lnstat:
add/remove: 0/1 grow/shrink: 1/0 up/down: 48/-486 (-438)
Total: Before=9960, After=9522, chg -4.40%
tipc/tipc:
add/remove: 0/0 grow/shrink: 1/1 up/down: 18/-62 (-44)
Total: Before=79182, After=79138, chg -0.06%
While at it, indent some strings which were starting at column 0,
and use tabs where possible, to have a consistent style across helps.
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
tc_pie_xstats->prob has a maximum value of (2^64 - 1).
Signed-off-by: Leslie Monis <lesliemonis@gmail.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
We have helper routines to support nested attribute addition into
netlink buffer: use them instead of open coding.
Use addattr_nest_compat()/addattr_nest_compat_end() where appropriate.
Signed-off-by: Serhey Popovych <serhe.popovych@gmail.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
This patch adapts the tc command line interface to allow bandwidth limits
to be specified as a percentage of the interface's capacity.
Adding this functionality requires passing the specified device string to
each class/qdisc which changes the prototype for a couple of functions: the
.parse_qopt and .parse_copt interfaces. The device string is a required
parameter for tc-qdisc and tc-class, and when not specified, the kernel
returns ENODEV. In this patch, if the user tries to specify a bandwidth
percentage without naming the device, we return an error from userspace.
Signed-off-by: Nishanth Devarajan<ndev2021@gmail.com>
When built with GCC warnings enabled:
q_pie.c: In function ‘pie_parse_opt’:
q_pie.c:78:38: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
(alpha > ALPHA_MAX) || (alpha < ALPHA_MIN)) {
^
q_pie.c:85:35: warning: comparison of unsigned expression < 0 is always false [-Wtype-limits]
(beta > BETA_MAX) || (beta < BETA_MIN)) {
^
This is because MIN is 0 and unsigned number can never be less than 0.
Therefore just remove the _MIN values.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Proportional Integral controller Enhanced (PIE) is a scheduler to address the
bufferbloat problem.
We present here a lightweight design, PIE(Proportional Integral controller
Enhanced) that can effectively control the average queueing latency to a target
value. Simulation results, theoretical analysis and Linux testbed results have
shown that PIE can ensure low latency and achieve high link utilization under
various congestion situations. The design does not require per-packet
timestamp, so it incurs very small overhead and is simple enough to implement
in both hardware and software. "
For more information, please see technical paper about PIE in the IEEE
Conference on High Performance Switching and Routing 2013. A copy of the paper
can be found at ftp://ftpeng.cisco.com/pie/.
Please also refer to the IETF draft submission at
http://tools.ietf.org/html/draft-pan-tsvwg-pie-00
All relevant code, documents and test scripts and results can be found at
ftp://ftpeng.cisco.com/pie/.
For problems with the iproute2/tc or Linux kernel code, please contact Vijay
Subramanian (vijaynsu@cisco.com or subramanian.vijay@gmail.com) Mythili Prabhu
(mysuryan@cisco.com)
Signed-off-by: Vijay Subramanian <subramanian.vijay@gmail.com>
Signed-off-by: Mythili Prabhu <mysuryan@cisco.com>
CC: Dave Taht <dave.taht@bufferbloat.net>
