Re: [Iperf-users] Iperf usage in Telecom network testing

Hi Joydev, Yes, the number of physical ports is limited by the hardware/host. The number of iperf flows is not, i.e. a single host can have multiple iperf streams. As standard testing there are no switches which iperf is compiled for. One would have to talk with the switch vendor to have them s

Re: [Iperf-users] issue in dual test and reverse mode of iperf 2.0.5

I'm currently prototyping --reverse mode for iperf2. Until it's released the firewall will need to be pierced using port forwarding for -r and -d. Sorry about that. Bob On Thu, Jun 15, 2017 at 11:53 PM, Pradeep Sahoo wrote: > We have seen the packets are being received by client in same networ

Re: [Iperf-users] Iperf usage in Telecom network testing

Hi Joydev, Sounds like an IXIA may be required. I spend most of my time in the wifi space and don't have current awareness of 10G testing at your scale. Testing 960G of IP traffic is quite a lot. The packet sizes will impact performance, e.g. smaller packets require more processing per byte tran

Re: [Iperf-users] Iperf for VxWorks

I don't know of a compile for vxworks but the source code is available for somebody could try. They would have to compile and test it, and probably port a few things - not really sure. Gnu automake is used and we could add support there once a compile from source was completed. Bob On Wed, Jul

[Iperf-users] v6 addressing improvements

Hi All, It looks like iperf2 could use some improvements with respect to v6 addressing. I'm considering the following: *The proposal is to restrict to v6 addresses when -V is set and allow for link local per the hints as well as support % for local device binding*. The user setting -V would get

[Iperf-users] iperf 2.0.10 release

Just a heads up that we just released iperf 2.0.10 on sourceforge . Change set includes: o Clean up help and man page for -V option o UDP IPv6: Default the mBuf size to 1450 for the client, default the Listener/server to 1470 o Display read/write buffer s

Re: [Iperf-users] Iperf3 - Througput showed on Output Report

iperf operates on network sockets and mostly operates at the transport layer. "The socket is primarily a concept used in the transport layer of the Internet model " https://en.wikipedia.org/wiki

Re: [Iperf-users] window multicast testing using iperf

Iperf 2.0.10 supports ip multicast. For example, to receive multicast on 239.1.1.1. issue - iperf -s -u -B 239.1.1.1 where the -B binds the multicast address to the host. This is required for the server to receive multicast. And to send issue use:

[Iperf-users] SSM support in iperf2

FYI, I just committed code into iperf2 which supports ip multicast SSM servers, both v4 and v6 )v6 requires the -V option.) It's linux only at the moment but OS X, Windows and FreeBSD are in the plans. Testing has been minimal. Bob --

Re: [Iperf-users] iperf port usage above port 5004

iperf 2.0.10 or greater on sourceforge should work. iperf 3 might a well. [root@localhost iperf2-code]# src/iperf -c 10.19.87.9 -i 1 -t 5 -p 9201 -B 10.19.87.8:9202 Client connecting to 10.19.8

[Iperf-users] iperf 2.0.11 new features

Hi All, Just a heads up about some new features planned for release in iperf 2.0.11 o) Isochronous transmission (requires clock synch, e.g. using PTP and quality oscillator) o) Burst transmissions (with vbr per a log distribution) o) UDP latency histogra

Re: [Iperf-users] Optimizing iPerf for achieving max transmission rate with UDP tests

I don't have much expertise in iperf3 so need to defer to those that do. >From a 2.0.11 perspective the limits tend to be the write syscall and the timestamp syscall. It might be interesting to compile the latest 2.0.11 alpha from sourceforge and use the -e (for enhanced reports) to see if write s

Re: [Iperf-users] client vs server

I don't really know for sure but my guess is that it's came from a TCP/UDP socket perspective, i.e. there is a server socket waiting for clients to connect to it. Or from a client/server perspective, the client initiates the test and the server accepts and responds to that. Also the "test result"

Re: [Iperf-users] Having problems with specifying different network interface for iperf3

For iperf2, the -B doesn't bind to an interface but only sets the source ip address in the packet. The routing tables decide the output interface. https://sourceforge.net/p/iperf2/discussion/general/thread/f856ae2c/ Here's an article: https://codingrelic.geekhold.com/2009/10/code-snippet-sobind

Re: [Iperf-users] Having problems with specifying different network interface for iperf3

I'd look at three things on both ends - iptables -L (or firewall settings) - routing tables (ip route show all) - arp tables (arp -n) and the mac addresses (ifconfig) to verify the end/end path. Also, if there are switches in the middle dumping the switch address tables may be required

Re: [Iperf-users] Bandwidth option (-b) doesn't seem to work

Curious if iperf2 exhibits similar behavior? It shouldn't have an issue with low packet rates. Bob On Mon, Apr 16, 2018 at 2:25 PM, Bruce A. Mah wrote: > If memory serves me right, Michael Fox wrote: > > The iperf3 bandwidth option doesn't seem to wo

Re: [Iperf-users] iperf3 and 100Gb

Seems reasonable to me though I'm not an iperf3 expert. Bob PS. As a side note, with iperf2 which does support multiple traffic threads, you can get 4 threads using -P 4. On Tue, Apr 17, 2018 at 6:19 AM, Jeffrey Lane wrote: > Hi all, > > I have what

Re: [Iperf-users] Multiple tests on the same port

2.0.5 is old and has multiple bugs so I wouldn't use it. Get a later version of that or try iperf 3 https://sourceforge.net/projects/iperf2/ http://software.es.net/iperf/obtaining.html 2.0 does support multiple clients. There is no fixed limit to the number of clients rather it will be limited

Re: [Iperf-users] iperf3: abrupt interval issue

what version of iperf did you use? iperf -v should provide that. If it's a later version of iperf2 the output on the client of with the -e option could be helpful. Bob On Thu, May 3, 2018 at 8:34 PM, Nikita Gupta wrote: > Hi Bruce thanks for giving time on this issue. > > I am working on an e

Re: [Iperf-users] iperf3: abrupt interval issue

The client output for 2.0.10 with -e and -i 1 could provide useful information. Bob On Mon, May 7, 2018 at 1:32 AM, Nikita Gupta wrote: > Hi Bob, > > Working without issue: iperf-2.0.10 > Time interval issue: iperf-3.3, iperf-3.1, iperf-3.5, iperf-3.0 > > Regards, > Nikita > > On Sat, May 5, 2

Re: [Iperf-users] iperf3: abrupt interval issue

iperf2 seems to be indicating 83 socket writes per second with no write errors. The congestion window is 42K and the RTT is 3.5 milliseconds. Nothing seems too unusual to me. Bob On Mon, May 7, 2018 at 8:05 PM, Nikita Gupta wrote: > Yeah Bob, > > Input command for iperf 2.0.10: > iperf -c -e

Re: [Iperf-users] iperf3: abrupt interval issue

Hi Nikita, I don't know the iperf3 code. We've been maintaining iperf2 mostly per WiFi testing needs. Bruce's original response suggested internal timers not firing on time. Bob On Tue, May 8, 2018 at 12:26 AM, Nikita Gupta wrote: > Yes, iperf2 giving correct result. But can you explain why

Re: [Iperf-users] iperf 3.1.3 TCP throughput issue

The tcptrace tool may provide insights. Also, if you can test without -R then a run with iperf2 and -e could provide confirmation of the expected throughputs and possibly some other information, e.g. the RTT samples. Also, with a 0.0

Re: [Iperf-users] iperf for periodic udp traffic?

Not sure on iperf3. iperf 2.0.11 supports isochronous traffic to better emulate things like video streams and will burst packets. It requires ./configure --enable-isochronous before make. The client command line option is --isochronous=:,

[Iperf-users] iperf 2.0.11 released

Hi All, We've just released iperf 2.0.11 tested across all supported platforms. Here are the significant changes: 2.0.11 change set (as of May 24th, 2018) o support for -b on server (read rate limiting) o support for --isochronous traffic with optional frames per second, mean and variance uses a

Re: [Iperf-users] iPerf Window size

Here is a good starting link: https://fasterdata.es.net/host-tuning/linux/ Speaking for iperf2, the -w window size sets the socket buffer size. There has been a lot of effort to reduce the windows per the buffer bloat problem . What exactly are you

Re: [Iperf-users] iperf for periodic udp traffic?

I'm not sure what is meant by "synchronous instead of isochronous." Bob On Sat, May 26, 2018 at 12:25 AM, Ashish Kashinath wrote: > Thanks for this! Is there a way to generate synchronous udp traffic > instead of it being isochronous? > > Regards, > > On Thu, May 24, 2018 at 8:08 PM, Bob McMaho

Re: [Iperf-users] iperf for periodic udp traffic?

That's how iperf works as is with -u UDP. The -b bandwidth setting combined with the -l payload length settings are used to calculate the interpacket gap or delay. The period is defined by this computed interpacket delay.Note that iperf is an application so the period sets the socket writes

Re: [Iperf-users] Using iperf on a looped circuit

I can't speak for iperf3, but I'm doubtful there is a way to do this with iperf 2 because the network stack's routing table is going make the forwarding decisions and it won't send things out that our destined to self. What platform are you using? If usi

Re: [Iperf-users] iPerf's impact to network

iperf generates traffic so it will use available bandwidth during the duration of the test (set by -t) or use the amount specified by -b. Bob On Thu, Jun 21, 2018 at 12:15 PM, Peter Grafton wrote: > Hello, > Can someone tell me what impact running iPerf on a live network will have > to users at

[Iperf-users] iperf 2.0.12 release

Hi All, We've released iperf 2.0.12 . Here are the latest set of changes since 2.0.10 2.0.11 change set (as of May 24th, 2018) o support for -b on server (read rate limiting) o honor -T (ttl) for unicast. (Note: the default value is 1 so

Re: [Iperf-users] Measure the amount of packets being processed by eth0 on Linux OS

With iperf 2 you may be able to estimate this. Use -b to set the network load and -P to set the number of traffic threads. The assumption is one traffic thread per core. Bob On Wed, Jul 11, 2018 at 12:02 PM, Kaushal Shriyan wrote: > > > On Thu, Jul 5, 2018 at 8:01 PM Kaushal Shriyan > wrot

Re: [Iperf-users] iperf3 query

I cant' speak to iperf 3, but from an iperf 2 perspective this level of "system testing" really isn't supported. Tools from ixia would be my suggestion. In general, it might be best to start with actionable effects, i.e what changes a test will effect. The

[Iperf-users] Netpower stat

FYI, I've added a network power stat to iperf 2's TCP enhanced output. It's mostly for convenience as there is no new information. Network power is defined as throughput / delay where the delay used is the sampled RTT per that report interval. Here's an example run: [root@localhost iperf2-code]#

[Iperf-users] Google's BBR

Below are two runs over wired GigE comparing Google's BBR with cubic. Note, for the network power the delay units are microseconds while the throughput are seconds. *A cubic run, netpower of 53532* [root@rjm-clubhouse-28 iperf2-code]# uname -r 4.17.9-20

Re: [Iperf-users] How does iperf UDP test count lost packets?

speaking for iperf2 , the iperf client writes a sequence number in every packet. The server then calculates the lost packets per the sequence number gaps. For iperf2, there is no test hanshake between client and server for basic UDP tests. Bob On Mon,

Re: [Iperf-users] iperf3 UDP not working with iptables drop random?

Can you share the iperf 2.0.13a output? Bob On Fri, Aug 17, 2018 at 1:07 PM, Hector Azpurua wrote: > Hi guys, > > I'm performing some local test on my network with iperf3 using UDP > connections between 2 Ubuntu 18.04 hosts. But it seems that the UDP i

Re: [Iperf-users] Iperf on Cisco Router/Switch

This is probably a question for Cisco and they would probably need to know which switch or router model. We don't see Cisco personnel on this list. Bob On Tue, Oct 23, 2018 at 9:48 AM Ashwajit Bhoutkar wrote: > Hi, > > Is it possible to install iPerf on a Cisco Router and Switch. If, yes, can

Re: [Iperf-users] Iperf on Cisco Router/Switch

Also, consider that iperf is a CPU based traffic system. I'm doubtful any of the router/switch CPUs could compete with modern server class systems. It may be better to connect 10G links to the switch/router and source traffic externally vs burden an router/switch CPU with this. For multiple traf

Re: [Iperf-users] UDP and QoS tests in Iperf3

With such high levels of oversubscription you might want to increase the socket buffer sizes (using -w) This will allow the network stack to accept the application level write() and "drop" them even if the wl driver and link is saturated. If the window size is too small the application write() ca

Re: [Iperf-users] UDP and QoS tests in Iperf3

VO AC may not use ampdu aggregation so double check that. The reason is that VO are small packet payloads (~200 bytes) and have low relative frequency of transmits. A wireless driver waiting around to fill an AMPDU from a VO queue will cause excessive latency and impact the voice session. Many

Re: [Iperf-users] UDP and QoS tests in Iperf3

Just an FYI, comparing a VO with 1 mpdu per ampdu vs 32 and small packets (minimize airtime.) If VO can break 10K pps it's most likely aggregating. [root@localhost iperf2-code]# wl -i ap0 ampdu_mpdu 1 root@localhost iperf2-code]# iperf -c 192.168.1.4 -u -S 0xC0 -b 40m -e -i 1 -t 10 -l 20

Re: [Iperf-users] UDP and QoS tests in Iperf3

Forgot to mention, be careful about the perspective of the measurement, i.e. tx or rx. Here's a run where the window is big enough such that the writes won't block and the TX offered load scales to the requested. The tx side os is dropping the packets ahead of the driver for this to occur. [root

Re: [Iperf-users] Compiled executable for Android

We cross compile 2.0.6+ for android. I don't do it myself, rather another engineer has been doing it. I'll follow up with him as I need to be able to do this myself. Bob On Mon, Dec 24, 2018 at 2:36 AM Ayrton Senna wrote: > Hi, > > I am finding it very difficult to cross-compile iperf2 for An

Re: [Iperf-users] Consulta

Speaking from an iperf 2 perspective, the systems generating and syncing traffic need to be considered. We qualify the computers we use to act as iperf traffic generators. It also depends on the operating systems as well. It also depends upon the capacity of the links under test. Bob On Wed,

Re: [Iperf-users] Calculating E2E delay and overhead from iperf results

Hi Karima, For iperf 2 use the -e option. This assumes the clocks on the client and server are synchronized to a level of the precision one cares about. We use a GPS disciplined oven controlled oscillator in our labs for a high quality reference then use

Re: [Iperf-users] Calculating E2E delay and overhead from iperf results

I don't think iperf3 supports this. I think you'll need to use iperf2. Bob On Fri, Jan 18, 2019 at 12:04 AM karima smida wrote: > Hi Bob, > First, thank you for your reply. Please, as I m a beginner, can you help > me with a solution with iperf3 and Synchronisation with NTP, a tutorial or > a

[Iperf-users] iperf 2.0.13 released today

FYI, iperf 2.0.13 is released on sourceforge https://sourceforge.net/projects/iperf2/ We've done a lot of testing with this version and added some new features. Information about it can be found on sourceforge. Bob ___ Iperf-users mailing list Iperf-u

Re: [Iperf-users] Framesize

For UDP (-u) the -l on the client defines the UDP payload size. A 1470 byte UDP payload will generate the max ethernet frame for ipv4 and 1450 bytes for ipv6. TCP is a byte protocol where there is no direct control of a layer 2 packet's frame size. The -l sets the write() size, -w the window si

Re: [Iperf-users] Throughput Testing of 100G Capacity using iPerf

I think it will be CPU constrained by the computer CPU and difficult to accomplish with one iperf stream. Also, you may want to qualify in terms of packets per second as that's likely the bottleneck. Iperf 2 has some experimental python 3 code in the flows directory that can coordinate multiple t

Re: [Iperf-users] Throughput Testing of 100G Capacity using iPerf

Can you run with iperf 2.0.13 using the same setup? I'd be curious to see how it performs compared to iperf 3. If you're able try this, please use the --realtime option to see if that helps. Bob On Thu, May 30, 2019 at 9:38 AM Chris Preimesberger

Re: [Iperf-users] Throughput Testing of 100G Capacity using iPerf

Is it just multiple threads? It might be interesting to try iperf 2.0.13 and the -P 8 option. Bob On Thu, May 30, 2019 at 10:04 AM Jeffrey Lane wrote: > I've been working on this a bit and the only way to get it was to run > multiple iperf3 threads. To do this, you have to set up several (we d

Re: [Iperf-users] Throughput Testing of 100G Capacity using iPerf

hmm, I confused. Did you run multiple iperf 3 sessions or iperf 2 with the -P 8,10 option or possibly both? Your previous response said the only way to get this was with multiple iperf 3 sessions and didn't mention iperf 2 nor the use of -P. In theory, iperf 2 could outperform iperf 3 per the us

Re: [Iperf-users] Throughput Testing of 100G Capacity using iPerf

Thanks. I'm curious to how much the threading helps performance here if at all. That part of the design we inherited from iperf 2 when we took over maintenance of it. We tried to keep the overall code similar in order to not impact performance. At first we tried not to touch the traffic threa

Re: [Iperf-users] Traffic test changing payload in virtual box

It sorta makes sense but not sure. My answers are from an iperf 2 perspective. Currently, there is no way from the command line to add a header to the UDP payload. It would have to be done in source code or by something like linux tc or ip tables. The iperf client doesn't require an iperf serv

Re: [Iperf-users] Traffic test changing payload in virtual box

Are you using UDP per -u? I assume so. What does "tcpdump arp or port " on the client's machine show? On my machines there will be packets even if there is no iperf server. They'll either be ARP requests or UDP packets. Also, the output of arp -n might be useful. The client can write even if th

Re: [Iperf-users] TCP performance Testing Question

Well, I can speak from an iperf2 and WiFi perspective. The main performance things to measure are speed (latency) and throughput. Throughput units is information over time, e.g. megabytes/second. Speed or latency is units time. Most people measure throughput and think that's enough. Network ad

Re: [Iperf-users] Request

I'd start with man iperf which should have examples (if you're using iperf 2.0.13) Bob ‪On Mon, Jun 24, 2019 at 1:53 AM ‫رغدة عبد via Iperf-users‬‎ < iperf-users@lists.sourceforge.net> wrote:‬ > Hello everyone I want the tutorials that guide me how to use iperf tcp and > iperf udp and how I can

[Iperf-users] iperf 2 "short term" road map

Hi All, I've been doing a lot of work on iperf 2 to handle new testing features with a focus on TCP latency testing. Please do let me know your thoughts or suggest comments per the list below. No promises on time frame as this is not my primary day job ;) The new features currently in developme

Re: [Iperf-users] Dummies guide to iperf

I think this is a very old version and will have performance problems. Maybe try a new version, https://sourceforge.net/projects/iperf2/files/iperf-2.0.13-win.exe/download more links here: https://iperf.fr/iperf-download.php#windows Bob On Mon, Aug 5, 2019 at 7:41 AM brent s. wrote: > Ashle

Re: [Iperf-users] iperf 3.7 - very wide bandwidth spreading

I think there is insufficient information here to make any meaningful educated guesses. Can you try with iperf 2.0.13 an use the -e option on both the client and server? Also, show the whole command line and describe the test setup, interconnecting networks, and all descriptions of competing traf

Re: [Iperf-users] iperf3 not working with sdn switches

It's very difficult to debug this with such limited information Iperf 3 does have a TCP connection before a UDP test. Iperf 2 doesn't. That's one possibility for a UDP test issue, i.e. something is prevented the initial TCP exchange. Bob On Fri, Sep 13, 2019 at 1:15 AM ha Fa wrote: > why iperf

Re: [Iperf-users] Regarding the bandwidth measurements considering UDP traffic

Iperf is an end/end measurement. It has no idea that an AP is even in the path. Bob On Fri, Sep 20, 2019 at 10:02 AM Bhanu Priya wrote: > Sir > I want to know the bandwidth measured by the iperf2.0.8 considers the load > on access point or not?. For example In a figure attached below if we are

Re: [Iperf-users] maximum allowed UDP bandwidth setting

I can't speak for iperf 3 but iperf 2.0.13 supports -b on the server for both TCP and UDP. It does this by running a simplified token bucket on the reads(). With that said, there is no way for a server to control the transmit rate of a iperf client running UDP because UDP is connectionless. TCP is

Re: [Iperf-users] maximum allowed UDP bandwidth setting

>> Consider also that the nature of iperf is to saturate the available channel. This isn't the case anymore for iperf 2.0.13 and greater. Saturating the channel has lots of negative effects with respect to testing per buffer bloat. 2.0.13 and greater has many features to support unsaturated chan

Re: [Iperf-users] Reg. Need to test TCP incast traffic using iperf

Speaking from an iperf 2 perspective, there are a few ways to control server 1 and server 2 traffic start times and burst sizes in iperf 2.0.13 + What operating systems are running on the servers? Can you synchronize the realtime clocks to a quality refer

Re: [Iperf-users] iperf on android

iperf 2.0.14a is currently under active development with multiple new features as well as 100G support. I haven't started the portability phase yet. So please don'

Re: [Iperf-users] Cygwin1.dll out of date

Bruce Mah at es net is my main iperf 3 contact. Not sure what you mean by "I hope they don't set a fixed size buffer" FYI, the current git head of iperf 2.0.14 hasn't undergone any windows testing yet. Not sure if it even compiles. The 2.0.13 tarball is the latest official release. We're getti

Re: [Iperf-users] Cygwin1.dll out of date

Cool, thanks for this Bob On Tue, Feb 4, 2020 at 2:07 PM Daniel Havey wrote: > Hi, I'm Daniel Havey from Microsoft Windows. I'm the PM for transports > (TCP/QUIC) and there is a bug in the cygwin1.dll that was distributed with > the iperf binaries. The bug limits maximum bandwidth achievable

Re: [Iperf-users] Cygwin1.dll out of date

I just checked with our windows engineer and he said the iperf 2 team no longer uses cygwin but rather builds a native version. Bob On Tue, Feb 4, 2020 at 2:07 PM Daniel Havey wrote: > Hi, I'm Daniel Havey from Microsoft Windows. I'm the PM for transpo

Re: [Iperf-users] Iperf latency measures

The UDP latency assumes the two clocks are synchronized. The GPS atomic clocks are suggested as a common reference. IEEE 1588 or Precision Time Protocol (PTP) is suggested (over things like network time protocol NTP) to distribute a reference clock. For a bench test environment one could use the c

Re: [Iperf-users] Iperf latency measures

The TCP display on the client is the round trip time (RTT) This is sampled per the network stack. Note that with 2.0.14 and the --trip-times option there is an application level latency as well. It's the client's write() start time to the server's final read of that write. For --isochronous the

Re: [Iperf-users] Negative Latency

There is no such thing as RTT on UDP packets, that's only for TCP. You're likely getting negative latencies for UDP because the clocks of the client and server aren't synchronized to a common quality time referençe. Bob On Sun, Apr 19, 2020 at 2:06 PM Andrew Morcos wrote: > > > Hello everyone,

Re: [Iperf-users] Multicast

What version of iperf where iperf -v should show this? Also, can you show the server and client side commands used? Finally, what operating system? Bob On Mon, May 4, 2020 at 7:47 AM Andrew Morcos wrote: > Hello guys, > > So I'm trying to bind multiple interfaces on a VM to a multicast addre

Re: [Iperf-users] Multicast on Iperf

What version of iperf? It it's iperf 2.0.13 use -B on the server to bind to the multicast address. Then just send to it on the client. -u is required for multicast. Also, for source specific multicast (SSM) -H sets the source. [root@localhost ~]# iperf -s -u -B 239.1.1.1 -i 1 -e --

Re: [Iperf-users] Filecopy only fast with iperf runs simultaneously

What version of iperf? Use iperf -v to tell. If you're using iperf 2.0.13 try posting the output of interval reports, -i 1 e.g., on both the client and server (tcp) along with the enhanced reports (use -e) for both cases, no SAMBA traffic and with concurre

Re: [Iperf-users] [UDP test] Increasing bitrate not increase the packet loss

Try to increase the window size with -w on the client. This will allow the operating system to accept the write and drop packets within the stack. If the window is too small the operating system will block the write until os buffers are available. Bob On Fri, Jul 31, 2020 at 8:56 AM Zufar Dhiya

Re: [Iperf-users] [UDP test] Increasing bitrate not increase the packet loss

If the bottleneck is the transmitter's wire that means things will back up behind that. The network stack on the client will queue packets. Since it's in a state of oversubscription there is no way for the client to ever drain the bottleneck so-to-speak. A bottleneck is when the service time is

Re: [Iperf-users] [UDP test] Increasing bitrate not increase the packet loss

Not at an intermediate network but at the host computer (or VM) that is transmitting Bob On Sun, Aug 2, 2020 at 6:49 PM Zufar Dhiyaulhaq wrote: > Hi Bob and Tim, > > Thank you for responding to my question. sometime today will try > increasing the window. Since I am testing this in a virtual en

Re: [Iperf-users] iperf-3.9 is available

Hi Bruce, With iperf 2 we limit the server read rate per -b or --bandwidth. Curious to why iperf 3 chose a different flag for this? Thanks, Bob On Mon, Aug 17, 2020 at 1:15 PM Bruce Mah wrote: > -BEGIN PGP SIGNED MESSAGE- > Hash: SHA512 > > ESnet (Energy Sciences Network) is proud to a

[Iperf-users] iperf 2.0.14 --sum-only option and TCP client ending timestamp

Hi All, We're adding a --sum-only option to iperf 2.0.14. This is useful for scaling the number of traffic threads to large values. Here is a sample output: [rjmcmahon@localhost iperf2-code]$ src/iperf -c 192.168.1.10 -i 1 -P 1000 --sum-only [SUM-1000] 0.0- 1.0 sec 1.57 GBytes 13.5 Gbits/sec

[Iperf-users] iperf 2.0.14 early field testing and shirts

Hi All, We're in an alpha and early field testing stage of iperf 2.0.14 testing and are soliciting testers. If you can help out contact me for details. We'll send you a shirt. If you just want a shirt, we'll sell them at cost. Contact me for that too. Yo

[Iperf-users] iperf 2 --full-duplex option

FYI, The iperf 2.0.14 now supports a --ful-duplex option. This is different than --bidir as it uses a single socket and treats it as full duplex. I'm noticing full duplex performance issues on some early redhat releases. I'm assuming it's not been tested much before. Man page notes: *Reverse,

[Iperf-users] iperf 2.0.14 EFT phase 2

Hi All, We're starting phase 2 EFT for iperf 2.0.14 . What defines phase 2 is that the shirts have arrived. Please do test this version. File a few bugs, suggest some output changes, or provide a patch and we'll send you some swag. Also, a key component o

[Iperf-users] pressure for better clocks

Hi All, Iperf 2.0.14 provides end/end latency measurements but requires sync'ed clocks. The lack of attention to latency is a major deficit to the networking industry and impairs user experience. I find one of the many problems with the tech industry is that cheap mass market stuff proliferates.

Re: [Iperf-users] Server/Client buffer size -d

Probably a bug. Can you try 2.0.14 ? You will have to compile from source. Bob On Thu, Nov 19, 2020 at 11:22 AM Valerio Scheleter via Iperf-users < iperf-users@lists.sourceforge.net> wrote: > Hello everyone, > > > > I am using iperf 2.0.9 with 1 client

Re: [Iperf-users] Server/Client buffer size -d

Try the docs and let me know. https://sourceforge.net/p/iperf2/code/ci/master/tree/INSTALL Bob On Fri, Nov 20, 2020 at 1:35 PM Valerio Scheleter < valerio.schele...@virginorbit.com> wrote: > Hi Bob, > > Thanks for your response. I honestly don't know how to build it from the > source code. Have

Re: [Iperf-users] Feature - Throughput ramp up

Hi Craig, Any reason you need iperf 3 for this and can't use iperf 2.0.14? We are in the process of early field test for iperf 2.0.14. This is probably an experimental feature that could be added last minute. We'd need you to test if willing. Our goal

Re: [Iperf-users] Feature - Throughput ramp up

Also, this would only be on the client. Iperf 2.0.14 supports both write and read rate limiting via -b on the server as well as client. Sweeps wouldn't be supported by the server (or on the read side.) Any issue with that, or, is there a read size need as well? Bob On Tue, Dec 1, 2020 at 11:29

Re: [Iperf-users] Feature - Throughput ramp up

For UDP, are you expecting the sweep applies both to client and server at the same time? I guess I'm confused about UDP read size rate limiting. If the client applies 100m and the server is read limited per a sweep there is going to be drops. UDP doesn't flow control the client. Bob On Tue, Dec

Re: [Iperf-users] Feature - Throughput ramp up

Ok, read side limiting would trigger source flow control for TCP and cause drops per UDP. Is that what you'd expect? Bob On Tue, Dec 1, 2020 at 11:36 AM Craig Reeves wrote: > Bob, > > Yes, we would need the Read side as well. Sometimes we see packets drop > from a single direction (that is act

Re: [Iperf-users] Feature - Throughput ramp up

This doesn't seem to require read side rate limiting. I think write side would do it. The full-duplex may be useful too. Then debug options are like: - iperf -c --full-duplex -u --sweep-range=1m,10m,1m --sweep-step 10 -i 1 -l 200 -S 0xc0 - iperf -c --reverse -u --sweep-range=1m,10m,1m

Re: [Iperf-users] Feature - Throughput ramp up

The flows code is likely broken at the moment. I've been focussed on iperf 2.0.14 itself. The basic requirement is ssh access to both ends used to create a flow via a python interpreter running 3.5 or greater (per the use of python's asyncio .) The

Re: [Iperf-users] Feature - Throughput ramp up

Ok, after some further discussions we've concluded this feature is best implemented by a script and not within iperf itself. The primary reason being is that an iperf client and iperf server don't have a feedback system per the "iperf protocol," i.e. stats on the server are not fed back to the clie

Re: [Iperf-users] Feature - Throughput ramp up

sure thing. We do a lot of sweeps so this seemed a natural thing to consider. It's just better done by a script for this type of request. We've considered hooking up a feedback path (similar to ful-duplex mode) were the server stats are fed back to the client in "real-time." It's a fair amount

Re: [Iperf-users] Feature - Throughput ramp up

l analysis. > > Tim > > > On 1 Dec 2020, at 23:52, Bob McMahon via Iperf-users < > iperf-users@lists.sourceforge.net> wrote: > > > > Ok, after some further discussions we've concluded this feature is best > implemented by a script and not within iperf

Re: [Iperf-users] Feature - Throughput ramp up

Go here https://sourceforge.net/projects/iperf/lists/iperf-users/unsubscribe Bob On Fri, Dec 4, 2020 at 2:24 AM shaukath ali via Iperf-users < iperf-users@lists.sourceforge.net> wrote: > Hi Mates, How to unsubscribe from this alias. Regds, Shaukath. > > From: Bob McMahon

[Iperf-users] iperf 2.0.14 experimental feature --near-congestion

Hi All, I've added an experimental feature to iperf 2.0.14 per option --near-congestion=. This is useful when measuring TCP write to read latencies at high throughput but not at bufferbloat. It requires a very much controlled network to be repeatable and,

[Iperf-users] iperf 2 request for feedback: --permit-key

Hi All, I'm working on support for a new option in iperf 2.0.14 currently called *--permit-key*. This prevents rogue or accidental access to an iperf server. It's expected that a script will set these values and pass them over a secure channel like ssh. Usage also expects -t to time out the serve

[Iperf-users] iperf 2.1 release candidate

FYI, An iperf 2.1 release candidate is ready. I've bumped the minor release number due to the amount of new features so it's iperf 2.1. Site is here. https://sourceforge.net/projects/iperf2/ Shirts will finally be going out for those that helped. Sorry for the delay. Thanks, Bob McMahon -- T

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