Jesper Dangaard Brouer 9ceb87fcea pktgen: document tuning for max NIC performance ... Using pktgen I'm seeing the ixgbe driver "push-back", due TX ring running full. Thus, the TX ring is artificially limiting pktgen. (Diagnose via "ethtool -S", look for "tx_restart_queue" or "tx_busy" counters.) Using ixgbe, the real reason behind the TX ring running full, is due to TX ring not being cleaned up fast enough. The ixgbe driver combines TX+RX ring cleanups, and the cleanup interval is affected by the ethtool --coalesce setting of parameter "rx-usecs". Do not increase the default NIC TX ring buffer or default cleanup interval. Instead simply document that pktgen needs special NIC tuning for maximum packet per sec performance. Performance results with pktgen with clone_skb=100000. TX ring size 512 (default), adjusting "rx-usecs": (Single CPU performance, E5-2630, ixgbe) - 3935002 pps - rx-usecs: 1 (irqs: 9346) - 5132350 pps - rx-usecs: 10 (irqs: 99157) - 5375111 pps - rx-usecs: 20 (irqs: 50154) - 5454050 pps - rx-usecs: 30 (irqs: 33872) - 5496320 pps - rx-usecs: 40 (irqs: 26197) - 5502510 pps - rx-usecs: 50 (irqs: 21527) TX ring size adjusting (ethtool -G), "rx-usecs==1" (default): - 3935002 pps - tx-size: 512 - 5354401 pps - tx-size: 768 - 5356847 pps - tx-size: 1024 - 5327595 pps - tx-size: 1536 - 5356779 pps - tx-size: 2048 - 5353438 pps - tx-size: 4096 Notice after commit 6f25cd47d (pktgen: fix xmit test for BQL enabled devices) pktgen uses netif_xmit_frozen_or_drv_stopped() and ignores the BQL "stack" pause (QUEUE_STATE_STACK_XOFF) flag. This allow us to put more pressure on the TX ring buffers. It is the ixgbe_maybe_stop_tx() call that stops the transmits, and pktgen respecting this in the call to netif_xmit_frozen_or_drv_stopped(txq). Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2014-07-01 15:50:23 -07:00
..
ABI	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next	2014-06-12 14:27:40 -07:00
accounting	Documentation/accounting/getdelays.c: add missing null-terminate after strncpy call	2014-06-23 16:47:44 -07:00
acpi	Documentation / ACPI: Fix location of GPIO documentation	2014-05-23 14:39:26 +02:00
aoe
arm	Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm into next	2014-06-05 15:57:04 -07:00
arm64	doc: arm64: add description of EFI stub support	2014-04-30 19:57:05 +01:00
auxdisplay
backlight
blackfin
block
blockdev	zram: propagate error to user	2014-04-07 16:36:02 -07:00
bus-devices
cdrom
cgroups	Merge branch 'for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup	2014-06-09 15:03:33 -07:00
connector	w1: optional bundling of netlink kernel replies	2014-05-27 13:56:21 -07:00
console
cpu-freq	cpufreq: add support for intermediate (stable) frequencies	2014-06-05 23:32:29 +02:00
cpuidle
cris
crypto
development-process
device-mapper	dm thin: add 'no_space_timeout' dm-thin-pool module param	2014-05-20 14:30:36 -04:00
devicetree	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net	2014-06-25 22:40:43 -07:00
DocBook	Documentation: Fix DocBook build with relative $(srctree)	2014-06-18 19:21:42 +02:00
driver-model	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next	2014-06-12 14:27:40 -07:00
dvb
early-userspace
EDID	drm: Add 800x600 (SVGA) screen resolution to the built-in EDIDs	2014-05-26 12:53:40 +10:00
extcon
fault-injection
fb	doc: spelling error changes	2014-05-05 15:32:05 +02:00
filesystems	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2014-06-12 10:30:18 -07:00
firmware_class
fmc
frv
gpio	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next	2014-06-04 08:50:34 -07:00
hid	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next	2014-06-04 08:50:34 -07:00
hwmon	hwmon: (ntc_thermistor) Use the manufacturer name properly	2014-06-25 07:09:13 -07:00
i2c	Documentation: i2c: improve section about flags mangling the protocol	2014-04-06 13:53:48 +02:00
i2o
ia64
ide
infiniband
input	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next	2014-06-04 08:50:34 -07:00
ioctl
isdn
ja_JP	Documentation: Update stable address in Chinese and Japanese translations	2014-04-16 14:13:27 -07:00
kbuild	kbuild: fix a typo in a kbuild document	2014-06-18 21:38:18 +02:00
kdump
ko_KR
laptops
leds
m68k
make
memory-devices
metag
mic
mips
misc-devices
mmc
mn10300
mtd	MTD updates for 3.16:	2014-06-11 08:35:34 -07:00
namespaces
netlabel
networking	pktgen: document tuning for max NIC performance	2014-07-01 15:50:23 -07:00
nfc
parisc
PCI
pcmcia
phy
platform	Documentation: Add list of laptop models supported by the Compal driver	2014-06-10 19:11:06 -04:00
power	PM / Documentation: Update copyright in suspend-and-cpuhotplug.txt	2014-06-09 22:54:15 +02:00
powerpc	Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc	2014-06-10 18:54:22 -07:00
pps
prctl
pti
ptp	ptp: In the testptp utility, use clock_adjtime from glibc when available	2014-06-16 21:32:31 -07:00
rapidio	rapidio: rework device hierarchy and introduce mport class of devices	2014-04-07 16:36:07 -07:00
RCU	documentation: Update API documentation	2014-04-29 08:38:53 -07:00
s390	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next	2014-06-04 08:50:34 -07:00
scheduler	asm/system.h: clean asm/system.h from docs	2014-04-07 16:36:11 -07:00
scsi	qla2xxx: Change copyright year to 2014 in all the source files.	2014-05-19 13:31:02 +02:00
security	Merge branch 'serge-next-1' of git://git.kernel.org/pub/scm/linux/kernel/git/sergeh/linux-security	2014-06-10 10:05:36 -07:00
serial	tty/serial: Add GPIOLIB helpers for controlling modem lines	2014-05-28 12:49:14 -07:00
sh
sound	doc: spelling error changes	2014-05-05 15:32:05 +02:00
spi	Merge remote-tracking branches 'spi/topic/s3c64xx', 'spi/topic/sc18is602', 'spi/topic/sh-hspi', 'spi/topic/sh-msiof', 'spi/topic/sh-sci', 'spi/topic/sirf' and 'spi/topic/spidev' into spi-next	2014-03-30 00:51:34 +00:00
sysctl	kernel/watchdog.c: print traces for all cpus on lockup detection	2014-06-23 16:47:44 -07:00
target
thermal	drm/nouveau/doc: update the thermal documentation	2014-06-17 14:50:17 +10:00
timers	timer_stats/doc: Fix /proc/timer_stats documentation	2014-05-04 20:46:32 +02:00
tpm
trace	Lots of tweaks, small fixes, optimizations, and some helper functions	2014-06-09 16:39:15 -07:00
usb	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next	2014-06-04 08:50:34 -07:00
vDSO	x86/vdso/doc: Make vDSO examples more portable	2014-06-12 19:01:24 -07:00
video4linux	[media] exynos4-is: Remove support for non-dt platforms	2014-05-23 18:52:54 -03:00
virtual	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next	2014-06-04 08:50:34 -07:00
vm	mm: mark remap_file_pages() syscall as deprecated	2014-06-06 16:08:17 -07:00
w1	w1: optional bundling of netlink kernel replies	2014-05-27 13:56:21 -07:00
watchdog	watchdog: it87_wdt: Work around non-working CIR interrupts	2014-03-31 13:33:55 +02:00
wimax
x86	Merge branch 'x86/espfix' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next	2014-06-05 07:46:15 -07:00
xtensa
zh_CN	driver core fixes for 3.15-rc2	2014-04-18 16:59:52 -07:00
.gitignore
00-INDEX	Merge branch 'x86-nuke-platforms-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2014-04-02 13:15:58 -07:00
applying-patches.txt
assoc_array.txt
atomic_ops.txt	arch,doc: Convert smp_mb__*()	2014-04-18 14:20:48 +02:00
bad_memory.txt
basic_profiling.txt
bcache.txt
binfmt_misc.txt
braille-console.txt
bt8xxgpio.txt
btmrvl.txt
BUG-HUNTING
bus-virt-phys-mapping.txt
cachetlb.txt
Changes	doc: Note need of bc in the kernel build from 3.10 onwards	2014-05-19 16:27:20 +02:00
circular-buffers.txt
clk.txt	clk: Improve clk_ops documentation	2014-05-12 17:08:33 -07:00
coccinelle.txt
CodingStyle	Documentation: expand/clarify debug documentation	2014-06-04 16:54:17 -07:00
cpu-hotplug.txt	Doc/cpu-hotplug: Specify race-free way to register CPU hotplug callbacks	2014-03-20 13:43:40 +01:00
cpu-load.txt
cputopology.txt
crc32.txt
dcdbas.txt
debugging-modules.txt
debugging-via-ohci1394.txt	firewire: revert to 4 GB RDMA, fix protocols using Memory Space	2014-05-29 15:50:30 +02:00
dell_rbu.txt
devices.txt	Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media	2014-04-04 09:50:07 -07:00
digsig.txt
DMA-API-HOWTO.txt	DMA-API: Update dma_pool_create ()and dma_pool_alloc() descriptions	2014-05-26 17:28:28 -06:00
DMA-API.txt	DMA-API: Capitalize "CPU" consistently	2014-05-26 17:28:27 -06:00
DMA-attributes.txt	doc: spelling error changes	2014-05-05 15:32:05 +02:00
dma-buf-sharing.txt	doc: spelling error changes	2014-05-05 15:32:05 +02:00
DMA-ISA-LPC.txt	DMA-API: Clarify physical/bus address distinction	2014-05-20 16:54:21 -06:00
dmaengine.txt
dmatest.txt
dontdiff	Documentation: LLVMLinux: Update Documentation/dontdiff	2014-04-09 13:44:34 -07:00
dynamic-debug-howto.txt	doc: spelling error changes	2014-05-05 15:32:05 +02:00
edac.txt	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next	2014-06-04 08:50:34 -07:00
efi-stub.txt	doc: arm64: add description of EFI stub support	2014-04-30 19:57:05 +01:00
eisa.txt
email-clients.txt	Documentation: update thunderbird email client settings	2014-05-25 12:39:00 -07:00
flexible-arrays.txt
futex-requeue-pi.txt	doc: fix double words	2014-03-21 13:16:58 +01:00
gcov.txt
highuid.txt
HOWTO
hsi.txt	Documentation: HSI: Add some general description for the HSI subsystem	2014-05-04 09:49:46 +02:00
hw_random.txt
hwspinlock.txt
init.txt
initrd.txt
intel_txt.txt
Intel-IOMMU.txt
io_ordering.txt
io-mapping.txt
iostats.txt
IPMI.txt
IRQ-affinity.txt
IRQ-domain.txt	genirq: Improve documentation to match current implementation	2014-05-27 10:16:44 +02:00
IRQ.txt
irqflags-tracing.txt	asm/system.h: clean asm/system.h from docs	2014-04-07 16:36:11 -07:00
isapnp.txt
java.txt	Documentation: update java sample wrapper for java 7	2014-05-25 12:39:00 -07:00
kernel-doc-nano-HOWTO.txt
kernel-docs.txt
kernel-parameters.txt	kernel/watchdog.c: print traces for all cpus on lockup detection	2014-06-23 16:47:44 -07:00
kernel-per-CPU-kthreads.txt
kmemcheck.txt	doc: fix double words	2014-03-21 13:16:58 +01:00
kmemleak.txt	mm: introduce kmemleak_update_trace()	2014-06-06 16:08:17 -07:00
kobject.txt
kprobes.txt	kprobes: Introduce NOKPROBE_SYMBOL() macro to maintain kprobes blacklist	2014-04-24 10:02:56 +02:00
kref.txt
ldm.txt
local_ops.txt
lockdep-design.txt
lockstat.txt
lockup-watchdogs.txt
logo.gif
logo.txt
magic-number.txt	Documentation/serial: Delete obsolete driver documentation	2014-04-16 14:20:34 -07:00
Makefile
ManagementStyle
md.txt
media-framework.txt
memory-barriers.txt	Documentation/memory-barriers.txt: fix important typo re memory barriers	2014-06-06 16:08:11 -07:00
memory-hotplug.txt	mm, hotplug: probe interface is available on several platforms	2014-06-23 16:47:43 -07:00
module-signing.txt	Nothing major: the stricter permissions checking for sysfs broke	2014-04-06 09:38:07 -07:00
mono.txt
mutex-design.txt	locking/mutexes: Documentation update/rewrite	2014-06-05 13:29:37 +02:00
nommu-mmap.txt
numastat.txt
oops-tracing.txt	Use 'E' instead of 'X' for unsigned module taint flag.	2014-03-31 14:52:43 +10:30
padata.txt
parport-lowlevel.txt
parport.txt
percpu-rw-semaphore.txt
phy.txt
pi-futex.txt
pinctrl.txt
pnp.txt
preempt-locking.txt
printk-formats.txt	doc: printk-formats: do not mention casts for u64/s64	2014-05-05 15:32:42 +02:00
pwm.txt	pwm: modify PWM_LOOKUP to initialize all struct pwm_lookup members	2014-05-21 11:19:36 +02:00
ramoops.txt
rbtree.txt	doc: spelling error changes	2014-05-05 15:32:05 +02:00
remoteproc.txt
rfkill.txt	doc: spelling error changes	2014-05-05 15:32:05 +02:00
robust-futex-ABI.txt
robust-futexes.txt	doc: spelling error changes	2014-05-05 15:32:05 +02:00
rpmsg.txt
rt-mutex-design.txt
rt-mutex.txt
rtc.txt
SAK.txt
SecurityBugs
serial-console.txt
sgi-ioc4.txt
SM501.txt
smsc_ece1099.txt
sparse.txt
spinlocks.txt
stable_api_nonsense.txt
stable_kernel_rules.txt	stable_kernel_rules: spelling/word usage	2014-04-16 14:13:26 -07:00
static-keys.txt
SubmitChecklist
SubmittingDrivers
SubmittingPatches	Documentation/SubmittingPatches: describe the Fixes: tag	2014-06-06 16:08:11 -07:00
svga.txt
sysfs-rules.txt
sysrq.txt
this_cpu_ops.txt
unaligned-memory-access.txt
unicode.txt
unshare.txt
vfio.txt
VGA-softcursor.txt
vgaarbiter.txt
video-output.txt
vme_api.txt
volatile-considered-harmful.txt
workqueue.txt
ww-mutex-design.txt
xz.txt
zorro.txt