k6 run ends up in fatal error

[mariomann]

Hi all,

Based on the blog post load test Grafana loki with Grafana k6 I want to load test my loki installation.
I try to use k6 with loki extension. I followed the installation guide but any test with a push method ends up with the fatal error.

$ ./k6 run ./basic_test.js

          /\      |‾‾| /‾‾/   /‾‾/
     /\  /  \     |  |/  /   /  /
    /  \/    \    |     (   /   ‾‾\
   /          \   |  |\  \ |  (‾)  |
  / __________ \  |__| \__\ \_____/ .io

WARN[0001] Running in multi-tenant-mode. Each VU has its own X-Scope-OrgID
  execution: local
     script: ./basic_test.js
     output: -

  scenarios: (100.00%) 1 scenario, 1 max VUs, 10m30s max duration (incl. graceful stop):
           * default: 1 iterations for each of 1 VUs (maxDuration: 10m0s, gracefulStop: 30s)

WARN[0001] Running in multi-tenant-mode. Each VU has its own X-Scope-OrgID
WARN[0001] Running in multi-tenant-mode. Each VU has its own X-Scope-OrgID
unexpected fault address 0x0
fatal error: fault
[signal SIGSEGV: segmentation violation code=0x80 addr=0x0 pc=0x465e3f]

You can find the hole go stack-trace as an attachment

I've tested it on MacOS 12.4 and Ubuntu 20.04.3 LTS (Focal Fossa) the same error on both systems.
Go-Version: go1.18.3 (both in MacOs and Ubuntu)

Am I doing something wrong? How can I solve the problem?

It is possible to query logs with the method instantQuery() but it's not possible to push any logs, neither with the push() method nor with the pushParameterized() Method.

Sample test:

import loki from 'k6/x/loki';

let conf = loki.Config("http://localhost:3100");
let client = loki.Client(conf);

export default () => {
   client.push();
};

[mstoykov]

Looking at the numbers of open panic issues in json-iterator ... it seems to me it might be a bad idea to use it ...

[WFSVK]

@mstoykov Could you, please, elaborate your thought?
Do you mean it requires deeper analyze and no workaround on user side?

[mstoykov]

Can you try both #42 and #43 and see if any of those help?

[mariomann]

Hi @mstoykov,

thx for your reply. I've tested it with #42 and #43 and it looks good to me 👍 no panic errors any more but successful load tests 😄

[mstoykov]

Thanks for testing 🙇