On Sat, 2 Feb 2019 at 18:54, ducasse <steph...@netcourrier.com> wrote: > On Sat, 2 Feb 2019 at 11:01, Ben Coman <b...@openinworld.com> wrote: > > > I am getting network errors trying to download latest Pharo Launcher, > > can you tell me how so that I try to reproduce it?
Since network performance depends a lot on location, and presuming you'd need to be at my house to reproduce my experience, I spent the afternoon learning about AWS so I could do some testing from a Australian based cloud box that you should be able to reproduce fairly easily, since this was my first time using AWS. With this 10 minute tutorial... [Launch a Linux Virtual Machine]( https://aws.amazon.com/getting-started/tutorials/launch-a-virtual-machine/) 1. Signed up and signed in Tip: I struggled a long while looping on "Sign in with root account credentials" until I discovered I needed to use the email address I signed up with, not the account name. [Edit:] In the top right between account name and support, pulled down list and selected "Asia Pacfic (Sydney)" 2. Clicked "Launch a virtual machine" (note, that only seems to show up for blank account, otherwise its "Launch Instance" 3. Ticked "Free tier only" filter. + Selected "Amazon Linux 2 AMI (HVM), SSD Volume Type" + Clicked <Review and Launch> (used default t2.micro) + Clicked <Launch> + From the pull-down selected "Create a new key pair", gave it a name and clicked <Download Keypair> saved as "SydneyPharoSpeedTest.pem" + Clicked <Launch Instance> + Clicked <View Instances> noted instance... * IP address: 54.252.136.78 * Zone: ap-southeast-2b * Security Group: Launch Wizard 1 4. On my Windows 10 box, in WSL did... $ cd ~/.ssh # if it doesn't exist, first do... mkdir -m 700 ~/.ssh $ cp /mnt/c/Users/Ben/Downloads/SydneyPharoSpeedTest.pem ~/.ssh $ chmod 400 ~/.ssh/SydneyPharoSpeedTest.pem $ ssh -i ~/.ssh/SydneyPharoSpeedTest.pem ubuntu@54.252.136.78$ cat /etc/os-release ID="amzn" ID_LIKE="centos rhel fedora" GOOD NETWORK BASELINE TEST... Ignoring any packet loss on poor networks, first testing low bandwidths on a good network $ vi test.sh #!/bin/sh if [ -d out ]; then dirdate=`stat -c %z out | awk '{print $1"-"$2}' ` mv out out.${dirdate} fi mkdir out for RATE in 1000k 500k 200k 100k 50k 20k 10k 5k 2k 1k do echo $RATE /usr/bin/time -f "%e" -o out/time.$RATE \ wget --quiet --limit-rate $RATE https://files.pharo.org/pharo-launcher/1.6/pharo-launcher-1.6.msi -O out/file.$RATE & done $ sh test.sh monitoring with... $ cat out/time* | sort -n $ ls -lS out results in following table and graphs... $RATE (kb/s) TIME (s) TIME (min) TIME (hr) 1000 54 1 0.0 500 105 2 0.0 200 259 4 0.1 100 515 9 0.1 50 1029 17 0.3 20 2576 43 0.7 10 5149 86 1.4 5 10527 175 2.9 [image: download-speed.png] Wow that surprised me. I'm not sure what the behaviour of file servers at low bandwidth should be, but intuitively the above seems odd. In the past troubleshooting seems to have been focused on the cause of slow speeds, but these can occur for many reasons unrelated to the the file server. The above test ignores cause to isolate behaviour at slow speeds. I forgot my own download speed yesterday (today is okay), but here is another sample... "(in Argentina) it is really slow ... 3.5KB/s ... average 10KB/s". http://forum.world.st/Pharo-Downloads-are-sluggish-td5084963.html I would hope that download time was near linear with speed all the way down to 1kb/s. Anyone have some sysadmins they can lean on to understand if that is realistic? The straightness of the line using a log-log axis makes it seem like policy rather than physics. [image: download-speed(log).png] HTH, cheers -ben
