6. Lagopus software switch command options and examples

Lagopus vswitch command options can be classified into 3 groups.

  • Global options
  • Intel DPDK options
  • Datapath options

Each option groups should be ordered and separated by -- (double dash) like below.

$ sudo lagopus [global options] [-- [dpdk options] [-- datapath options] ]

Example:
$ sudo lagopus -l lagopus.log -- -c3 -n1 -- -p7
               <-  global  ->    <-dpdk->   <-datapath->

Examples of how to use options are described in Lagopus command line examples later in this section.

6.1. Global option

All mandatory options are marked (Mandatory). Others are optional.

-d Run in debug mode
-v Show version
--version Show version
-h Show help
--help Show help
-l filename Specify a log/trace file path [default: syslog]
--logfile filename
 Specify a log/trace file path [default: syslog]
-p filename Specify a pid file path [default: /var/run/lt-lagopus.pid]
--pidfile filename
 Specify a pid file path [default: /var/run/lt-lagopus.pid]
-C filename Specify a configuration file (DSL format) path
--config filename
 Specify a configuration file (DSL format) path

6.2. Intel DPDK Option

All mandatory options are marked (Mandatory). Others are optional.

  • -c : (Mandatory)

    • Speicify which CPU cores are assigned to Lagopus with a hex bitmask of CPU port to use

    • Example: -c9

      • Only CPU core 0 and core 3 are assigned, then let bit0 and bit3 on.
      • 0x1001 (binary) = 9 (Hexadecimal)

  • -n : (Mandatory)

    • Specify number of memory channel which CPU supports

    • Range: 1,2,4

    • Example: -n2

      • a CPU supports dual memory channlel

  • -m :

    • Specify how much Hugepage memory is assigned to Lagopus in mega byte.

    • Maximum hugepage memory is assigned if no option is specified.

    • Example: -m 512

      • Use 512MB for Lagopus

  • --socket-mem :

    • Specify how much Hugepage memory for each CPU socket is assigned to Lagopus in mega byte.
    • This option is exclusive with -m option

6.3. Datapath option

All mandatory options are marked (Mandatory). Others are optional.

6.3.1. Common option

  • --no-cache :

    • Don’t use flow cache [default: use flow cache]

  • --fifoness TYPE :

    • Select packet ordering (FIFOness) mode [default: flow]

    • none : FIFOness is disabled

    • port : FIFOness per each port.

    • flow : FIFOness per each flow.

    • Example: --fifoness none

      • Specify flow-level FIFOness

  • --hashtype TYPE :

    • Select key-value store type for flow cache [default: intel64]

    • intel64 : Hash with Intel CRC32 and XOR (64bit)

    • city64 : CityHash (64bit)

    • murmur3 : MurmurHash3 (32bit)

    • Example: --hashtype city64

      • Use CityHash

  • --kvstype TYPE :

    • Select key-value store type for flow cache [default: hashmap_nolock]

    • hashmap_nolock : Use hashmap without reader and writer lock

    • hashmap : Use hashmap with reader and writer lock

    • ptree : Use patricia tree

    • Example: --kvstype ptree

      • Use patricia tree for key-value store

6.3.2. CPU core and packet processing

Dataplane of Lagopus provides two options to assign CPU core and packet processing worker.

  • Automatic assignment option
  • Explicit assignment option

These options are exclusive.

6.3.2.1. Automatic assignment option

  • -p PORTMASK :

    • hexadecimal bitmask of ports to be used
    • Example: -p3
      • Use port 0 and port 1
    • Since Lagpous v0.2.8, this option has become optional when any port is specified in lagopus.dsl.
      • Only specified ports in lagopus.dsl are used.

  • -w NWORKERS:

    • number of packet processing worker [default: assign as possible]

    • System assigns CPU core automatically.

    • Example: -w8

      • Use total 8 cores for data plane

  • --core-assign TYPE:

    • Select automatically core assign policy [default: performance]
    • performance : Don’t use HTT core. (e.g. use only 8 cores on 8C16T processor)
    • balance : Use HTT core (e.g. use 16 cores on 8C16T processor)
    • minimum : Use only one core.

6.3.2.2. Explicit assignment option

Current Lagopus limitation: youngest core number can not be specified among available CPU cores.

  • --rx "(PORT, QUEUE, CORE),(PORT, QUEUE, CORE),...,(PORT, QUEUE, CORE)":

    • List NIC RX assignment policy of NIC RX port, queue, and CPU core with the combination of (PORT, QUEUE, CORE) and “,”

    • PORT : Port number [0 - n]

    • QUEUE: Queue number [default: 0]

    • CORE : CPU core number

    • Example: --rx '(0,0,2),(1,0,3)'

      Assign port 0 to CPU core #2 and port 1 to CPU core #3

  • --tx "(PORT,CORE),(PORT,CORE),...,(PORT,CORE)":

    • List NIC TX assignment policy of NIC TX port and CPU core with the combination of (PORT, CORE) and “,”

    • PORT: Port number [0 - n]

    • CORE: CPU core number

    • Example: --tx '(0,4),(1,5)'

      Assign port 0 TX to CPU core #4 and port 1 TX to CPU core #5

  • --w "CORE, ..., CORE":

    • List of the CPU cores for packet processing with “,”

      • Example: --w '8,9,10,11,12,13,14,15'

        Assign CPU core 8 - 15 for packet processing

6.4. Lagopus command line examples

6.4.1. Simple run

  • CPU core: 1 and 2
  • Number of memory channel: 1
  • NIC port: 0 and 1
  • Packet processing workers are automatically assigned to CPU cores.
  • Run in debug-mode
$ sudo lagopus -d -- -c3 -n1 -- -p3

6.4.2. Run with explicit assignment to achieve maximum performance

  • CPU core: 1 - 7
    • core # 2 for I/O RX
    • core # 3 for I/O TX
    • core # 4, # 5, #6, # 7 for packet processing
  • Memory channel: 2
  • NIC port: 0 and 1
  • Run in debug-mode
$ sudo lagopus -d -- -cfe -n2 -- --rx '(0,0,2),(1,0,2)' --tx '(0,3),(1,3)' --w 4,5,6,7

6.4.3. Run with packet-ordering in flow-level

  • CPU core: 1 - 15
  • Memory channel: 2
  • NIC port: 0, 1, 2
  • Worker assignment is automatic
  • FIFOness option to ensure packet-ordering in flow-levle
$ sudo lagopus -- -cfffe -n2 -- -p7 --fifoness flow