[deliverable/linux.git] / Documentation / networking / pktgen.txt



                  HOWTO for the linux packet generator 
                  ------------------------------------

Date: 041221

Enable CONFIG_NET_PKTGEN to compile and build pktgen.o either in kernel
or as module. Module is preferred. insmod pktgen if needed. Once running
pktgen creates a thread on each CPU where each thread has affinity to its CPU.
Monitoring and controlling is done via /proc. Easiest to select a suitable 
a sample script and configure.

On a dual CPU:

ps aux | grep pkt
root       129  0.3  0.0     0    0 ?        SW    2003 523:20 [pktgen/0]
root       130  0.3  0.0     0    0 ?        SW    2003 509:50 [pktgen/1]


For monitoring and control pktgen creates:
	/proc/net/pktgen/pgctrl
	/proc/net/pktgen/kpktgend_X
        /proc/net/pktgen/ethX


Tuning NIC for max performance
==============================

The default NIC setting are (likely) not tuned for pktgen's artificial
overload type of benchmarking, as this could hurt the normal use-case.

Specifically increasing the TX ring buffer in the NIC:
 # ethtool -G ethX tx 1024

A larger TX ring can improve pktgen's performance, while it can hurt
in the general case, 1) because the TX ring buffer might get larger
than the CPUs L1/L2 cache, 2) because it allow more queueing in the
NIC HW layer (which is bad for bufferbloat).

One should be careful to conclude, that packets/descriptors in the HW
TX ring cause delay.  Drivers usually delay cleaning up the
ring-buffers (for various performance reasons), thus packets stalling
the TX ring, might just be waiting for cleanup.

This cleanup issues is specifically the case, for the driver ixgbe
(Intel 82599 chip).  This driver (ixgbe) combine TX+RX ring cleanups,
and the cleanup interval is affected by the ethtool --coalesce setting
of parameter "rx-usecs".

For ixgbe use e.g "30" resulting in approx 33K interrupts/sec (1/30*10^6):
 # ethtool -C ethX rx-usecs 30


Viewing threads
===============
/proc/net/pktgen/kpktgend_0 
Name: kpktgend_0  max_before_softirq: 10000
Running: 
Stopped: eth1 
Result: OK: max_before_softirq=10000

Most important the devices assigned to thread. Note! A device can only belong 
to one thread.


Viewing devices
===============

Parm section holds configured info. Current hold running stats. 
Result is printed after run or after interruption. Example:

/proc/net/pktgen/eth1       

Params: count 10000000  min_pkt_size: 60  max_pkt_size: 60
     frags: 0  delay: 0  clone_skb: 1000000  ifname: eth1
     flows: 0 flowlen: 0
     dst_min: 10.10.11.2  dst_max: 
     src_min:   src_max: 
     src_mac: 00:00:00:00:00:00  dst_mac: 00:04:23:AC:FD:82
     udp_src_min: 9  udp_src_max: 9  udp_dst_min: 9  udp_dst_max: 9
     src_mac_count: 0  dst_mac_count: 0 
     Flags: 
Current:
     pkts-sofar: 10000000  errors: 39664
     started: 1103053986245187us  stopped: 1103053999346329us idle: 880401us
     seq_num: 10000011  cur_dst_mac_offset: 0  cur_src_mac_offset: 0
     cur_saddr: 0x10a0a0a  cur_daddr: 0x20b0a0a
     cur_udp_dst: 9  cur_udp_src: 9
     flows: 0
Result: OK: 13101142(c12220741+d880401) usec, 10000000 (60byte,0frags)
  763292pps 390Mb/sec (390805504bps) errors: 39664

Configuring threads and devices
================================
This is done via the /proc interface easiest done via pgset in the scripts

Examples:

 pgset "clone_skb 1"     sets the number of copies of the same packet
 pgset "clone_skb 0"     use single SKB for all transmits
 pgset "burst 8"         uses xmit_more API to queue 8 copies of the same
                         packet and update HW tx queue tail pointer once.
                         "burst 1" is the default
 pgset "pkt_size 9014"   sets packet size to 9014
 pgset "frags 5"         packet will consist of 5 fragments
 pgset "count 200000"    sets number of packets to send, set to zero
                         for continuous sends until explicitly stopped.

 pgset "delay 5000"      adds delay to hard_start_xmit(). nanoseconds

 pgset "dst 10.0.0.1"    sets IP destination address
                         (BEWARE! This generator is very aggressive!)

 pgset "dst_min 10.0.0.1"            Same as dst
 pgset "dst_max 10.0.0.254"          Set the maximum destination IP.
 pgset "src_min 10.0.0.1"            Set the minimum (or only) source IP.
 pgset "src_max 10.0.0.254"          Set the maximum source IP.
 pgset "dst6 fec0::1"     IPV6 destination address
 pgset "src6 fec0::2"     IPV6 source address
 pgset "dstmac 00:00:00:00:00:00"    sets MAC destination address
 pgset "srcmac 00:00:00:00:00:00"    sets MAC source address

 pgset "queue_map_min 0" Sets the min value of tx queue interval
 pgset "queue_map_max 7" Sets the max value of tx queue interval, for multiqueue devices
                         To select queue 1 of a given device,
                         use queue_map_min=1 and queue_map_max=1

 pgset "src_mac_count 1" Sets the number of MACs we'll range through.  
                         The 'minimum' MAC is what you set with srcmac.

 pgset "dst_mac_count 1" Sets the number of MACs we'll range through.
                         The 'minimum' MAC is what you set with dstmac.

 pgset "flag [name]"     Set a flag to determine behaviour.  Current flags
                         are: IPSRC_RND # IP source is random (between min/max)
                              IPDST_RND # IP destination is random
                              UDPSRC_RND, UDPDST_RND,
                              MACSRC_RND, MACDST_RND
                              TXSIZE_RND, IPV6,
                              MPLS_RND, VID_RND, SVID_RND
                              FLOW_SEQ,
                              QUEUE_MAP_RND # queue map random
                              QUEUE_MAP_CPU # queue map mirrors smp_processor_id()
                              UDPCSUM,
                              IPSEC # IPsec encapsulation (needs CONFIG_XFRM)
                              NODE_ALLOC # node specific memory allocation

 pgset spi SPI_VALUE     Set specific SA used to transform packet.

 pgset "udp_src_min 9"   set UDP source port min, If < udp_src_max, then
                         cycle through the port range.

 pgset "udp_src_max 9"   set UDP source port max.
 pgset "udp_dst_min 9"   set UDP destination port min, If < udp_dst_max, then
                         cycle through the port range.
 pgset "udp_dst_max 9"   set UDP destination port max.

 pgset "mpls 0001000a,0002000a,0000000a" set MPLS labels (in this example
                                         outer label=16,middle label=32,
					 inner label=0 (IPv4 NULL)) Note that
					 there must be no spaces between the
					 arguments. Leading zeros are required.
					 Do not set the bottom of stack bit,
					 that's done automatically. If you do
					 set the bottom of stack bit, that
					 indicates that you want to randomly
					 generate that address and the flag
					 MPLS_RND will be turned on. You
					 can have any mix of random and fixed
					 labels in the label stack.

 pgset "mpls 0"		  turn off mpls (or any invalid argument works too!)

 pgset "vlan_id 77"       set VLAN ID 0-4095
 pgset "vlan_p 3"         set priority bit 0-7 (default 0)
 pgset "vlan_cfi 0"       set canonical format identifier 0-1 (default 0)

 pgset "svlan_id 22"      set SVLAN ID 0-4095
 pgset "svlan_p 3"        set priority bit 0-7 (default 0)
 pgset "svlan_cfi 0"      set canonical format identifier 0-1 (default 0)

 pgset "vlan_id 9999"     > 4095 remove vlan and svlan tags
 pgset "svlan 9999"       > 4095 remove svlan tag


 pgset "tos XX"           set former IPv4 TOS field (e.g. "tos 28" for AF11 no ECN, default 00)
 pgset "traffic_class XX" set former IPv6 TRAFFIC CLASS (e.g. "traffic_class B8" for EF no ECN, default 00)

 pgset stop    	          aborts injection. Also, ^C aborts generator.

 pgset "rate 300M"        set rate to 300 Mb/s
 pgset "ratep 1000000"    set rate to 1Mpps

Example scripts
===============

A collection of small tutorial scripts for pktgen is in examples dir.

pktgen.conf-1-1                  # 1 CPU 1 dev 
pktgen.conf-1-2                  # 1 CPU 2 dev
pktgen.conf-2-1                  # 2 CPU's 1 dev 
pktgen.conf-2-2                  # 2 CPU's 2 dev
pktgen.conf-1-1-rdos             # 1 CPU 1 dev w. route DoS 
pktgen.conf-1-1-ip6              # 1 CPU 1 dev ipv6
pktgen.conf-1-1-ip6-rdos         # 1 CPU 1 dev ipv6  w. route DoS
pktgen.conf-1-1-flows            # 1 CPU 1 dev multiple flows.

Run in shell: ./pktgen.conf-X-Y It does all the setup including sending. 


Interrupt affinity
===================
Note when adding devices to a specific CPU there good idea to also assign 
/proc/irq/XX/smp_affinity so the TX-interrupts gets bound to the same CPU.
as this reduces cache bouncing when freeing skb's.

Enable IPsec
============
Default IPsec transformation with ESP encapsulation plus Transport mode
could be enabled by simply setting:

pgset "flag IPSEC"
pgset "flows 1"

To avoid breaking existing testbed scripts for using AH type and tunnel mode,
user could use "pgset spi SPI_VALUE" to specify which formal of transformation
to employ.


Current commands and configuration options
==========================================

** Pgcontrol commands:

start
stop

** Thread commands:

add_device
rem_device_all
max_before_softirq


** Device commands:

count
clone_skb
debug

frags
delay

src_mac_count
dst_mac_count

pkt_size 
min_pkt_size
max_pkt_size

mpls

udp_src_min
udp_src_max

udp_dst_min
udp_dst_max

flag
  IPSRC_RND
  IPDST_RND
  UDPSRC_RND
  UDPDST_RND
  MACSRC_RND
  MACDST_RND
  TXSIZE_RND
  IPV6
  MPLS_RND
  VID_RND
  SVID_RND
  FLOW_SEQ
  QUEUE_MAP_RND
  QUEUE_MAP_CPU
  UDPCSUM
  IPSEC
  NODE_ALLOC

dst_min
dst_max

src_min
src_max

dst_mac
src_mac

clear_counters

dst6
src6

flows
flowlen

rate
ratep

References:
ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/
ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/examples/

Paper from Linux-Kongress in Erlangen 2004.
ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/pktgen_paper.pdf

Thanks to:
Grant Grundler for testing on IA-64 and parisc, Harald Welte,  Lennert Buytenhek
Stephen Hemminger, Andi Kleen, Dave Miller and many others.


Good luck with the linux net-development.
Commit	Line	Data
1da177e4 LT	1
	2
	3	HOWTO for the linux packet generator
	4	------------------------------------
	5
	6	Date: 041221
	7
	8	Enable CONFIG_NET_PKTGEN to compile and build pktgen.o either in kernel
	9	or as module. Module is preferred. insmod pktgen if needed. Once running
3f6dee9b	10	pktgen creates a thread on each CPU where each thread has affinity to its CPU.
1da177e4 LT	11	Monitoring and controlling is done via /proc. Easiest to select a suitable
	12	a sample script and configure.
	13
	14	On a dual CPU:
	15
	16	ps aux \| grep pkt
	17	root 129 0.3 0.0 0 0 ? SW 2003 523:20 [pktgen/0]
	18	root 130 0.3 0.0 0 0 ? SW 2003 509:50 [pktgen/1]
	19
	20
2fe0ae78	21	For monitoring and control pktgen creates:
1da177e4 LT	22	/proc/net/pktgen/pgctrl
	23	/proc/net/pktgen/kpktgend_X
	24	/proc/net/pktgen/ethX
	25
	26
9ceb87fc JDB	27	Tuning NIC for max performance
	28	==============================
	29
	30	The default NIC setting are (likely) not tuned for pktgen's artificial
	31	overload type of benchmarking, as this could hurt the normal use-case.
	32
	33	Specifically increasing the TX ring buffer in the NIC:
	34	# ethtool -G ethX tx 1024
	35
	36	A larger TX ring can improve pktgen's performance, while it can hurt
	37	in the general case, 1) because the TX ring buffer might get larger
	38	than the CPUs L1/L2 cache, 2) because it allow more queueing in the
	39	NIC HW layer (which is bad for bufferbloat).
	40
	41	One should be careful to conclude, that packets/descriptors in the HW
	42	TX ring cause delay. Drivers usually delay cleaning up the
	43	ring-buffers (for various performance reasons), thus packets stalling
	44	the TX ring, might just be waiting for cleanup.
	45
	46	This cleanup issues is specifically the case, for the driver ixgbe
	47	(Intel 82599 chip). This driver (ixgbe) combine TX+RX ring cleanups,
	48	and the cleanup interval is affected by the ethtool --coalesce setting
	49	of parameter "rx-usecs".
	50
	51	For ixgbe use e.g "30" resulting in approx 33K interrupts/sec (1/30*10^6):
	52	# ethtool -C ethX rx-usecs 30
	53
	54
1da177e4 LT	55	Viewing threads
	56	===============
	57	/proc/net/pktgen/kpktgend_0
	58	Name: kpktgend_0 max_before_softirq: 10000
	59	Running:
	60	Stopped: eth1
	61	Result: OK: max_before_softirq=10000
	62
3f6dee9b	63	Most important the devices assigned to thread. Note! A device can only belong
1da177e4 LT	64	to one thread.
	65
	66
	67	Viewing devices
	68	===============
	69
	70	Parm section holds configured info. Current hold running stats.
	71	Result is printed after run or after interruption. Example:
	72
	73	/proc/net/pktgen/eth1
	74
	75	Params: count 10000000 min_pkt_size: 60 max_pkt_size: 60
	76	frags: 0 delay: 0 clone_skb: 1000000 ifname: eth1
	77	flows: 0 flowlen: 0
	78	dst_min: 10.10.11.2 dst_max:
	79	src_min: src_max:
	80	src_mac: 00:00:00:00:00:00 dst_mac: 00:04:23:AC:FD:82
	81	udp_src_min: 9 udp_src_max: 9 udp_dst_min: 9 udp_dst_max: 9
	82	src_mac_count: 0 dst_mac_count: 0
	83	Flags:
	84	Current:
	85	pkts-sofar: 10000000 errors: 39664
	86	started: 1103053986245187us stopped: 1103053999346329us idle: 880401us
	87	seq_num: 10000011 cur_dst_mac_offset: 0 cur_src_mac_offset: 0
	88	cur_saddr: 0x10a0a0a cur_daddr: 0x20b0a0a
	89	cur_udp_dst: 9 cur_udp_src: 9
	90	flows: 0
	91	Result: OK: 13101142(c12220741+d880401) usec, 10000000 (60byte,0frags)
	92	763292pps 390Mb/sec (390805504bps) errors: 39664
	93
5d3f083d ML	94	Configuring threads and devices
5d3f083d ML	95	================================
1da177e4 LT	96	This is done via the /proc interface easiest done via pgset in the scripts
	97
	98	Examples:
	99
	100	pgset "clone_skb 1" sets the number of copies of the same packet
	101	pgset "clone_skb 0" use single SKB for all transmits
38b2cf29 AS	102	pgset "burst 8" uses xmit_more API to queue 8 copies of the same
	103	packet and update HW tx queue tail pointer once.
	104	"burst 1" is the default
1da177e4 LT	105	pgset "pkt_size 9014" sets packet size to 9014
	106	pgset "frags 5" packet will consist of 5 fragments
	107	pgset "count 200000" sets number of packets to send, set to zero
d0f19d82	108	for continuous sends until explicitly stopped.
1da177e4 LT	109
	110	pgset "delay 5000" adds delay to hard_start_xmit(). nanoseconds
	111
	112	pgset "dst 10.0.0.1" sets IP destination address
	113	(BEWARE! This generator is very aggressive!)
	114
	115	pgset "dst_min 10.0.0.1" Same as dst
	116	pgset "dst_max 10.0.0.254" Set the maximum destination IP.
	117	pgset "src_min 10.0.0.1" Set the minimum (or only) source IP.
	118	pgset "src_max 10.0.0.254" Set the maximum source IP.
	119	pgset "dst6 fec0::1" IPV6 destination address
	120	pgset "src6 fec0::2" IPV6 source address
	121	pgset "dstmac 00:00:00:00:00:00" sets MAC destination address
	122	pgset "srcmac 00:00:00:00:00:00" sets MAC source address
	123
896a7cf8 ED	124	pgset "queue_map_min 0" Sets the min value of tx queue interval
	125	pgset "queue_map_max 7" Sets the max value of tx queue interval, for multiqueue devices
	126	To select queue 1 of a given device,
	127	use queue_map_min=1 and queue_map_max=1
	128
1da177e4 LT	129	pgset "src_mac_count 1" Sets the number of MACs we'll range through.
	130	The 'minimum' MAC is what you set with srcmac.
	131
	132	pgset "dst_mac_count 1" Sets the number of MACs we'll range through.
	133	The 'minimum' MAC is what you set with dstmac.
	134
	135	pgset "flag [name]" Set a flag to determine behaviour. Current flags
72f8e06f MK	136	are: IPSRC_RND # IP source is random (between min/max)
	137	IPDST_RND # IP destination is random
	138	UDPSRC_RND, UDPDST_RND,
	139	MACSRC_RND, MACDST_RND
	140	TXSIZE_RND, IPV6,
f0e82fd0	141	MPLS_RND, VID_RND, SVID_RND
72f8e06f	142	FLOW_SEQ,
896a7cf8 ED	143	QUEUE_MAP_RND # queue map random
896a7cf8 ED	144	QUEUE_MAP_CPU # queue map mirrors smp_processor_id()
72f8e06f MK	145	UDPCSUM,
	146	IPSEC # IPsec encapsulation (needs CONFIG_XFRM)
	147	NODE_ALLOC # node specific memory allocation
896a7cf8	148
e5f79d11	149	pgset spi SPI_VALUE Set specific SA used to transform packet.
1da177e4 LT	150
	151	pgset "udp_src_min 9" set UDP source port min, If < udp_src_max, then
	152	cycle through the port range.
	153
	154	pgset "udp_src_max 9" set UDP source port max.
	155	pgset "udp_dst_min 9" set UDP destination port min, If < udp_dst_max, then
	156	cycle through the port range.
	157	pgset "udp_dst_max 9" set UDP destination port max.
	158
ca6549af SW	159	pgset "mpls 0001000a,0002000a,0000000a" set MPLS labels (in this example
	160	outer label=16,middle label=32,
	161	inner label=0 (IPv4 NULL)) Note that
	162	there must be no spaces between the
	163	arguments. Leading zeros are required.
	164	Do not set the bottom of stack bit,
fa00e7e1	165	that's done automatically. If you do
ca6549af SW	166	set the bottom of stack bit, that
	167	indicates that you want to randomly
	168	generate that address and the flag
	169	MPLS_RND will be turned on. You
	170	can have any mix of random and fixed
	171	labels in the label stack.
	172
	173	pgset "mpls 0" turn off mpls (or any invalid argument works too!)
	174
f0e82fd0 FF	175	pgset "vlan_id 77" set VLAN ID 0-4095
	176	pgset "vlan_p 3" set priority bit 0-7 (default 0)
	177	pgset "vlan_cfi 0" set canonical format identifier 0-1 (default 0)
	178
	179	pgset "svlan_id 22" set SVLAN ID 0-4095
	180	pgset "svlan_p 3" set priority bit 0-7 (default 0)
	181	pgset "svlan_cfi 0" set canonical format identifier 0-1 (default 0)
	182
	183	pgset "vlan_id 9999" > 4095 remove vlan and svlan tags
	184	pgset "svlan 9999" > 4095 remove svlan tag
	185
	186
	187	pgset "tos XX" set former IPv4 TOS field (e.g. "tos 28" for AF11 no ECN, default 00)
	188	pgset "traffic_class XX" set former IPv6 TRAFFIC CLASS (e.g. "traffic_class B8" for EF no ECN, default 00)
	189
1da177e4 LT	190	pgset stop aborts injection. Also, ^C aborts generator.
1da177e4 LT	191
43d28b65 DT	192	pgset "rate 300M" set rate to 300 Mb/s
43d28b65 DT	193	pgset "ratep 1000000" set rate to 1Mpps
1da177e4 LT	194
	195	Example scripts
	196	===============
	197
fff9289b	198	A collection of small tutorial scripts for pktgen is in examples dir.
1da177e4 LT	199
	200	pktgen.conf-1-1 # 1 CPU 1 dev
	201	pktgen.conf-1-2 # 1 CPU 2 dev
	202	pktgen.conf-2-1 # 2 CPU's 1 dev
	203	pktgen.conf-2-2 # 2 CPU's 2 dev
	204	pktgen.conf-1-1-rdos # 1 CPU 1 dev w. route DoS
	205	pktgen.conf-1-1-ip6 # 1 CPU 1 dev ipv6
	206	pktgen.conf-1-1-ip6-rdos # 1 CPU 1 dev ipv6 w. route DoS
	207	pktgen.conf-1-1-flows # 1 CPU 1 dev multiple flows.
	208
	209	Run in shell: ./pktgen.conf-X-Y It does all the setup including sending.
	210
	211
	212	Interrupt affinity
	213	===================
	214	Note when adding devices to a specific CPU there good idea to also assign
	215	/proc/irq/XX/smp_affinity so the TX-interrupts gets bound to the same CPU.
	216	as this reduces cache bouncing when freeing skb's.
	217
e5f79d11 FD	218	Enable IPsec
	219	============
	220	Default IPsec transformation with ESP encapsulation plus Transport mode
	221	could be enabled by simply setting:
	222
	223	pgset "flag IPSEC"
	224	pgset "flows 1"
	225
	226	To avoid breaking existing testbed scripts for using AH type and tunnel mode,
	227	user could use "pgset spi SPI_VALUE" to specify which formal of transformation
	228	to employ.
	229
1da177e4 LT	230
	231	Current commands and configuration options
	232	==========================================
	233
	234	** Pgcontrol commands:
	235
	236	start
	237	stop
	238
	239	** Thread commands:
	240
	241	add_device
	242	rem_device_all
	243	max_before_softirq
	244
	245
	246	** Device commands:
	247
	248	count
	249	clone_skb
	250	debug
	251
	252	frags
	253	delay
	254
	255	src_mac_count
	256	dst_mac_count
	257
	258	pkt_size
	259	min_pkt_size
	260	max_pkt_size
	261
ca6549af SW	262	mpls
ca6549af SW	263
1da177e4 LT	264	udp_src_min
	265	udp_src_max
	266
	267	udp_dst_min
	268	udp_dst_max
	269
	270	flag
	271	IPSRC_RND
1da177e4 LT	272	IPDST_RND
	273	UDPSRC_RND
	274	UDPDST_RND
	275	MACSRC_RND
	276	MACDST_RND
72f8e06f MK	277	TXSIZE_RND
	278	IPV6
	279	MPLS_RND
	280	VID_RND
	281	SVID_RND
	282	FLOW_SEQ
	283	QUEUE_MAP_RND
	284	QUEUE_MAP_CPU
	285	UDPCSUM
e5f79d11	286	IPSEC
72f8e06f	287	NODE_ALLOC
1da177e4 LT	288
	289	dst_min
	290	dst_max
	291
	292	src_min
	293	src_max
	294
	295	dst_mac
	296	src_mac
	297
	298	clear_counters
	299
	300	dst6
	301	src6
	302
	303	flows
	304	flowlen
	305
43d28b65 DT	306	rate
	307	ratep
	308
1da177e4 LT	309	References:
	310	ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/
	311	ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/examples/
	312
	313	Paper from Linux-Kongress in Erlangen 2004.
	314	ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/pktgen_paper.pdf
	315
	316	Thanks to:
	317	Grant Grundler for testing on IA-64 and parisc, Harald Welte, Lennert Buytenhek
	318	Stephen Hemminger, Andi Kleen, Dave Miller and many others.
	319
	320
ca6549af	321	Good luck with the linux net-development.