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|
# SPDX-License-Identifier: GPL-2.0-only
#
# Traffic control configuration.
#
menuconfig NET_SCHED
bool "QoS and/or fair queueing"
select NET_SCH_FIFO
---help---
When the kernel has several packets to send out over a network
device, it has to decide which ones to send first, which ones to
delay, and which ones to drop. This is the job of the queueing
disciplines, several different algorithms for how to do this
"fairly" have been proposed.
If you say N here, you will get the standard packet scheduler, which
is a FIFO (first come, first served). If you say Y here, you will be
able to choose from among several alternative algorithms which can
then be attached to different network devices. This is useful for
example if some of your network devices are real time devices that
need a certain minimum data flow rate, or if you need to limit the
maximum data flow rate for traffic which matches specified criteria.
This code is considered to be experimental.
To administer these schedulers, you'll need the user-level utilities
from the package iproute2+tc at
<https://www.kernel.org/pub/linux/utils/net/iproute2/>. That package
also contains some documentation; for more, check out
<http://www.linuxfoundation.org/collaborate/workgroups/networking/iproute2>.
This Quality of Service (QoS) support will enable you to use
Differentiated Services (diffserv) and Resource Reservation Protocol
(RSVP) on your Linux router if you also say Y to the corresponding
classifiers below. Documentation and software is at
<http://diffserv.sourceforge.net/>.
If you say Y here and to "/proc file system" below, you will be able
to read status information about packet schedulers from the file
/proc/net/psched.
The available schedulers are listed in the following questions; you
can say Y to as many as you like. If unsure, say N now.
if NET_SCHED
comment "Queueing/Scheduling"
config NET_SCH_CBQ
tristate "Class Based Queueing (CBQ)"
---help---
Say Y here if you want to use the Class-Based Queueing (CBQ) packet
scheduling algorithm. This algorithm classifies the waiting packets
into a tree-like hierarchy of classes; the leaves of this tree are
in turn scheduled by separate algorithms.
See the top of <file:net/sched/sch_cbq.c> for more details.
CBQ is a commonly used scheduler, so if you're unsure, you should
say Y here. Then say Y to all the queueing algorithms below that you
want to use as leaf disciplines.
To compile this code as a module, choose M here: the
module will be called sch_cbq.
config NET_SCH_HTB
tristate "Hierarchical Token Bucket (HTB)"
---help---
Say Y here if you want to use the Hierarchical Token Buckets (HTB)
packet scheduling algorithm. See
<http://luxik.cdi.cz/~devik/qos/htb/> for complete manual and
in-depth articles.
HTB is very similar to CBQ regarding its goals however is has
different properties and different algorithm.
To compile this code as a module, choose M here: the
module will be called sch_htb.
config NET_SCH_HFSC
tristate "Hierarchical Fair Service Curve (HFSC)"
---help---
Say Y here if you want to use the Hierarchical Fair Service Curve
(HFSC) packet scheduling algorithm.
To compile this code as a module, choose M here: the
module will be called sch_hfsc.
config NET_SCH_ATM
tristate "ATM Virtual Circuits (ATM)"
depends on ATM
---help---
Say Y here if you want to use the ATM pseudo-scheduler. This
provides a framework for invoking classifiers, which in turn
select classes of this queuing discipline. Each class maps
the flow(s) it is handling to a given virtual circuit.
See the top of <file:net/sched/sch_atm.c> for more details.
To compile this code as a module, choose M here: the
module will be called sch_atm.
config NET_SCH_PRIO
tristate "Multi Band Priority Queueing (PRIO)"
---help---
Say Y here if you want to use an n-band priority queue packet
scheduler.
To compile this code as a module, choose M here: the
module will be called sch_prio.
config NET_SCH_MULTIQ
tristate "Hardware Multiqueue-aware Multi Band Queuing (MULTIQ)"
---help---
Say Y here if you want to use an n-band queue packet scheduler
to support devices that have multiple hardware transmit queues.
To compile this code as a module, choose M here: the
module will be called sch_multiq.
config NET_SCH_RED
tristate "Random Early Detection (RED)"
---help---
Say Y here if you want to use the Random Early Detection (RED)
packet scheduling algorithm.
See the top of <file:net/sched/sch_red.c> for more details.
To compile this code as a module, choose M here: the
module will be called sch_red.
config NET_SCH_SFB
tristate "Stochastic Fair Blue (SFB)"
---help---
Say Y here if you want to use the Stochastic Fair Blue (SFB)
packet scheduling algorithm.
See the top of <file:net/sched/sch_sfb.c> for more details.
To compile this code as a module, choose M here: the
module will be called sch_sfb.
config NET_SCH_SFQ
tristate "Stochastic Fairness Queueing (SFQ)"
---help---
Say Y here if you want to use the Stochastic Fairness Queueing (SFQ)
packet scheduling algorithm.
See the top of <file:net/sched/sch_sfq.c> for more details.
To compile this code as a module, choose M here: the
module will be called sch_sfq.
config NET_SCH_TEQL
tristate "True Link Equalizer (TEQL)"
---help---
Say Y here if you want to use the True Link Equalizer (TLE) packet
scheduling algorithm. This queueing discipline allows the combination
of several physical devices into one virtual device.
See the top of <file:net/sched/sch_teql.c> for more details.
To compile this code as a module, choose M here: the
module will be called sch_teql.
config NET_SCH_TBF
tristate "Token Bucket Filter (TBF)"
---help---
Say Y here if you want to use the Token Bucket Filter (TBF) packet
scheduling algorithm.
See the top of <file:net/sched/sch_tbf.c> for more details.
To compile this code as a module, choose M here: the
module will be called sch_tbf.
config NET_SCH_CBS
tristate "Credit Based Shaper (CBS)"
---help---
Say Y here if you want to use the Credit Based Shaper (CBS) packet
scheduling algorithm.
See the top of <file:net/sched/sch_cbs.c> for more details.
To compile this code as a module, choose M here: the
module will be called sch_cbs.
config NET_SCH_ETF
tristate "Earliest TxTime First (ETF)"
help
Say Y here if you want to use the Earliest TxTime First (ETF) packet
scheduling algorithm.
See the top of <file:net/sched/sch_etf.c> for more details.
To compile this code as a module, choose M here: the
module will be called sch_etf.
config NET_SCH_TAPRIO
tristate "Time Aware Priority (taprio) Scheduler"
help
Say Y here if you want to use the Time Aware Priority (taprio) packet
scheduling algorithm.
See the top of <file:net/sched/sch_taprio.c> for more details.
To compile this code as a module, choose M here: the
module will be called sch_taprio.
config NET_SCH_GRED
tristate "Generic Random Early Detection (GRED)"
---help---
Say Y here if you want to use the Generic Random Early Detection
(GRED) packet scheduling algorithm for some of your network devices
(see the top of <file:net/sched/sch_red.c> for details and
references about the algorithm).
To compile this code as a module, choose M here: the
module will be called sch_gred.
config NET_SCH_DSMARK
tristate "Differentiated Services marker (DSMARK)"
---help---
Say Y if you want to schedule packets according to the
Differentiated Services architecture proposed in RFC 2475.
Technical information on this method, with pointers to associated
RFCs, is available at <http://www.gta.ufrj.br/diffserv/>.
To compile this code as a module, choose M here: the
module will be called sch_dsmark.
config NET_SCH_NETEM
tristate "Network emulator (NETEM)"
---help---
Say Y if you want to emulate network delay, loss, and packet
re-ordering. This is often useful to simulate networks when
testing applications or protocols.
To compile this driver as a module, choose M here: the module
will be called sch_netem.
If unsure, say N.
config NET_SCH_DRR
tristate "Deficit Round Robin scheduler (DRR)"
help
Say Y here if you want to use the Deficit Round Robin (DRR) packet
scheduling algorithm.
To compile this driver as a module, choose M here: the module
will be called sch_drr.
If unsure, say N.
config NET_SCH_MQPRIO
tristate "Multi-queue priority scheduler (MQPRIO)"
help
Say Y here if you want to use the Multi-queue Priority scheduler.
This scheduler allows QOS to be offloaded on NICs that have support
for offloading QOS schedulers.
To compile this driver as a module, choose M here: the module will
be called sch_mqprio.
If unsure, say N.
config NET_SCH_SKBPRIO
tristate "SKB priority queue scheduler (SKBPRIO)"
help
Say Y here if you want to use the SKB priority queue
scheduler. This schedules packets according to skb->priority,
which is useful for request packets in DoS mitigation systems such
as Gatekeeper.
To compile this driver as a module, choose M here: the module will
be called sch_skbprio.
If unsure, say N.
config NET_SCH_CHOKE
tristate "CHOose and Keep responsive flow scheduler (CHOKE)"
help
Say Y here if you want to use the CHOKe packet scheduler (CHOose
and Keep for responsive flows, CHOose and Kill for unresponsive
flows). This is a variation of RED which trys to penalize flows
that monopolize the queue.
To compile this code as a module, choose M here: the
module will be called sch_choke.
config NET_SCH_QFQ
tristate "Quick Fair Queueing scheduler (QFQ)"
help
Say Y here if you want to use the Quick Fair Queueing Scheduler (QFQ)
packet scheduling algorithm.
To compile this driver as a module, choose M here: the module
will be called sch_qfq.
If unsure, say N.
config NET_SCH_CODEL
tristate "Controlled Delay AQM (CODEL)"
help
Say Y here if you want to use the Controlled Delay (CODEL)
packet scheduling algorithm.
To compile this driver as a module, choose M here: the module
will be called sch_codel.
If unsure, say N.
config NET_SCH_FQ_CODEL
tristate "Fair Queue Controlled Delay AQM (FQ_CODEL)"
help
Say Y here if you want to use the FQ Controlled Delay (FQ_CODEL)
packet scheduling algorithm.
To compile this driver as a module, choose M here: the module
will be called sch_fq_codel.
If unsure, say N.
config NET_SCH_CAKE
tristate "Common Applications Kept Enhanced (CAKE)"
help
Say Y here if you want to use the Common Applications Kept Enhanced
(CAKE) queue management algorithm.
To compile this driver as a module, choose M here: the module
will be called sch_cake.
If unsure, say N.
config NET_SCH_FQ
tristate "Fair Queue"
help
Say Y here if you want to use the FQ packet scheduling algorithm.
FQ does flow separation, and is able to respect pacing requirements
set by TCP stack into sk->sk_pacing_rate (for localy generated
traffic)
To compile this driver as a module, choose M here: the module
will be called sch_fq.
If unsure, say N.
config NET_SCH_HHF
tristate "Heavy-Hitter Filter (HHF)"
help
Say Y here if you want to use the Heavy-Hitter Filter (HHF)
packet scheduling algorithm.
To compile this driver as a module, choose M here: the module
will be called sch_hhf.
config NET_SCH_PIE
tristate "Proportional Integral controller Enhanced (PIE) scheduler"
help
Say Y here if you want to use the Proportional Integ
|