perfSONAR User Q&A and Other Discussion

[Brian Candler <>]

On 15/06/2017 14:22, Andrew Lake wrote:
> By default, we randomize the intervals somewhere between 1x the 
> interval and 2x the interval (so they run every 1-2 hours in your 
> case). Tests are recreated every 24 hours to prevent orphaned tests if 
> a meshconfig-agent goes away, so my guess is the 20 minute spacing is 
> when one ends and the other begins We have done interval randomization 
> for a number of years for a few reasons, but the biggest being so 
> tests are less likely to stack on top of each other. Without the 
> randomization, your command-line tests are much more likely to have to 
> wait long time to run if you run them at the beginning of your 
> interval vs the end. 

ISTM that could also be achieved by staggering tests within the 
interval: e.g. if a test has a 6-hour interval but has 12 remote 
endpoints, then run a test to one host in turn every 30 minutes. That 
would be a lot more deterministic.  Asking for a test every 6 hours, but 
in practice sometimes not having one done for 12 hours, seems less than 
ideal.

I tried to look at some pscheduler schedule output.  Here I'm looking at 
one host which has a single throughput test with 1 hour interval, 
testing to two other hosts (XX.XX.97.10 and XX.XX.99.253).

The full results I get from "pscheduler schedule 
--filter-test=throughput +PT4H" are at the end of the mail.

Looking at just those tests with --source XX.XX.97.10 --ip-version 4 
--dest XX.XX.97.14, they are scheduled for:

2017-06-16T01:08:13Z - 2017-06-16T01:08:42Z
2017-06-16T01:54:33Z - 2017-06-16T01:55:02Z
2017-06-16T02:50:22Z - 2017-06-16T02:50:51Z
2017-06-16T04:25:40Z - 2017-06-16T04:26:09Z

Those are intervals of approx 46 minutes, 56 minutes and 1h 45 minutes 
respectively, which seems to disagree with the assertion that they are 
randomised to "somewhere between 1x the interval and 2x the interval".

Aside: to drive pscheduler, the reference I'm using is 
http://fasterdata.es.net/performance-testing/network-troubleshooting-tools/pscheduler. 
This is the only documentation I have found, and it's mainly examples 
for bwctl users.  Is there something which documents the full set of flags?

Regards,

Brian.


$ pscheduler schedule --filter-test=throughput +PT4H

2017-06-16T01:08:13Z - 2017-06-16T01:08:42Z  (Pending)
throughput --duration PT20S --source XX.XX.97.10 --ip-version 4 --dest
  XX.XX.97.14 --parallel 1 (Run with tool 'iperf3')
https://perfsonar-core.example.edu/pscheduler/tasks/6cfe4d66-bdf4-438d-bdee-f20d5692e2bd/runs/2eb5ec3d-188e-4451-af1b-5c42378c3f70


2017-06-16T01:11:52Z - 2017-06-16T01:12:21Z  (Pending)
throughput --duration PT20S --source XX.XX.97.14 --ip-version 4 --dest
  XX.XX.99.253 --parallel 1 (Run with tool 'iperf3')
https://perfsonar-core.example.edu/pscheduler/tasks/892f72c7-ce2b-4e1b-9502-bb99bcbfcc4c/runs/e9d6d49d-555c-46cf-ae2a-a6eedc9f7b07


2017-06-16T01:54:33Z - 2017-06-16T01:55:02Z  (Pending)
throughput --duration PT20S --source XX.XX.97.10 --ip-version 4 --dest
  XX.XX.97.14 --parallel 1 (Run with tool 'iperf3')
https://perfsonar-core.example.edu/pscheduler/tasks/6cfe4d66-bdf4-438d-bdee-f20d5692e2bd/runs/9d36196a-039d-413b-a783-95d5344dda1c


2017-06-16T01:56:30Z - 2017-06-16T01:56:59Z  (Pending)
throughput --duration PT20S --source XX.XX.97.14 --ip-version 4 --dest
  XX.XX.97.10 --parallel 1 (Run with tool 'iperf3')
https://perfsonar-core.example.edu/pscheduler/tasks/5d49ad9a-3b15-4e86-890a-0d066fc1ebe0/runs/9a287c52-8715-427a-9686-7a52a5cc423f


2017-06-16T02:00:18Z - 2017-06-16T02:00:47Z  (Pending)
throughput --duration PT20S --source XX.XX.99.253 --ip-version 4 --dest
  XX.XX.97.14 --parallel 1 (Run with tool 'iperf3')
https://perfsonar-core.example.edu/pscheduler/tasks/b547d025-13b3-4c34-bf3c-971e0f0b0430/runs/d7df72e8-1460-402c-8bed-ab77101ff9eb


2017-06-16T02:18:36Z - 2017-06-16T02:19:05Z  (Pending)
throughput --duration PT20S --source XX.XX.97.14 --ip-version 4 --dest
  XX.XX.99.253 --parallel 1 (Run with tool 'iperf3')
https://perfsonar-core.example.edu/pscheduler/tasks/892f72c7-ce2b-4e1b-9502-bb99bcbfcc4c/runs/85ecb0a6-f2e3-403c-a84a-74c30b16bc91


2017-06-16T02:50:22Z - 2017-06-16T02:50:51Z  (Pending)
throughput --duration PT20S --source XX.XX.97.10 --ip-version 4 --dest
  XX.XX.97.14 --parallel 1 (Run with tool 'iperf3')
https://perfsonar-core.example.edu/pscheduler/tasks/6cfe4d66-bdf4-438d-bdee-f20d5692e2bd/runs/f0231e3e-a971-4025-8b4d-350b5824e70d


2017-06-16T02:50:59Z - 2017-06-16T02:51:28Z  (Pending)
throughput --duration PT20S --source XX.XX.97.14 --ip-version 4 --dest
  XX.XX.99.253 --parallel 1 (Run with tool 'iperf3')
https://perfsonar-core.example.edu/pscheduler/tasks/892f72c7-ce2b-4e1b-9502-bb99bcbfcc4c/runs/7c028a80-c71e-4531-bb7c-aebd3510a4bb


2017-06-16T02:57:51Z - 2017-06-16T02:58:20Z  (Pending)
throughput --duration PT20S --source XX.XX.97.14 --ip-version 4 --dest
  XX.XX.97.10 --parallel 1 (Run with tool 'iperf3')
https://perfsonar-core.example.edu/pscheduler/tasks/5d49ad9a-3b15-4e86-890a-0d066fc1ebe0/runs/f80d9ec9-cfd5-4173-bbc8-d197c6e313b1


2017-06-16T03:26:21Z - 2017-06-16T03:26:50Z  (Pending)
throughput --duration PT20S --source XX.XX.99.253 --ip-version 4 --dest
  XX.XX.97.14 --parallel 1 (Run with tool 'iperf3')
https://perfsonar-core.example.edu/pscheduler/tasks/b547d025-13b3-4c34-bf3c-971e0f0b0430/runs/ab5e9906-3942-4bfc-a3d0-dadcdf4519e2


2017-06-16T04:23:07Z - 2017-06-16T04:23:36Z  (Pending)
throughput --duration PT20S --source XX.XX.97.14 --ip-version 4 --dest
  XX.XX.97.10 --parallel 1 (Run with tool 'iperf3')
https://perfsonar-core.example.edu/pscheduler/tasks/5d49ad9a-3b15-4e86-890a-0d066fc1ebe0/runs/b383d218-b0f3-4fa8-8d82-3d27fcdfeb62


2017-06-16T04:23:38Z - 2017-06-16T04:24:07Z  (Pending)
throughput --duration PT20S --source XX.XX.97.14 --ip-version 4 --dest
  XX.XX.99.253 --parallel 1 (Run with tool 'iperf3')
https://perfsonar-core.example.edu/pscheduler/tasks/892f72c7-ce2b-4e1b-9502-bb99bcbfcc4c/runs/05411945-8436-42b0-9598-dbddf8dda18e


2017-06-16T04:25:40Z - 2017-06-16T04:26:09Z  (Pending)
throughput --duration PT20S --source XX.XX.97.10 --ip-version 4 --dest
  XX.XX.97.14 --parallel 1 (Run with tool 'iperf3')
https://perfsonar-core.example.edu/pscheduler/tasks/6cfe4d66-bdf4-438d-bdee-f20d5692e2bd/runs/12265824-ad6b-4d2a-b380-c0d1f4a22be1


2017-06-16T04:26:19Z - 2017-06-16T04:26:48Z  (Pending)
throughput --duration PT20S --source XX.XX.99.253 --ip-version 4 --dest
  XX.XX.97.14 --parallel 1 (Run with tool 'iperf3')
https://perfsonar-core.example.edu/pscheduler/tasks/b547d025-13b3-4c34-bf3c-971e0f0b0430/runs/dca8b7b6-ce6d-4878-a48d-30e76a5e9f92


2017-06-16T04:35:03Z - 2017-06-16T04:35:32Z  (Pending)
throughput --duration PT20S --source XX.XX.97.14 --ip-version 4 --dest
  XX.XX.97.10 --parallel 1 (Run with tool 'iperf3')
https://perfsonar-core.example.edu/pscheduler/tasks/5d49ad9a-3b15-4e86-890a-0d066fc1ebe0/runs/c93433c7-dce0-48fc-9872-af72e501cf5b


2017-06-16T04:42:20Z - 2017-06-16T04:42:49Z  (Pending)
throughput --duration PT20S --source XX.XX.99.253 --ip-version 4 --dest
  XX.XX.97.14 --parallel 1 (Run with tool 'iperf3')
https://perfsonar-core.example.edu/pscheduler/tasks/b547d025-13b3-4c34-bf3c-971e0f0b0430/runs/9a458869-a761-440e-9947-bed47f5bec38


2017-06-16T04:45:11Z - 2017-06-16T04:45:40Z  (Pending)
throughput --duration PT20S --source XX.XX.97.14 --ip-version 4 --dest
  XX.XX.99.253 --parallel 1 (Run with tool 'iperf3')
https://perfsonar-core.example.edu/pscheduler/tasks/892f72c7-ce2b-4e1b-9502-bb99bcbfcc4c/runs/41da08ba-3a56-4dcf-a35f-c42bbd3fa997