codeceptjs / codeceptjs/CodeceptJS

codeceptjs run-workers X can do with sequencing improvements

Open
#4,250 6 comments 2 reactions 1 assignee Assigned to @Copilot View on GitHub
stale
Dominant language
JavaScript
Stars
4.2k
Forks
757
Avg merge
2d 9h
Merged PRs (30d)
16

Description

#### What are you trying to achieve?

`codeceptjs run-workers 5` should be more performant and pull tests from a pool instead of having each test pre-assigned to a thread

#### What do you get instead?

Currently run-workers will create a pool of all tests when `codeceptjs run-workers 5` is executed.

It then pre-assigns each test to a CPU thread and starts running all tests assigned to each thread.

This creates an even distribution of tests per thread. The problem is that not all tests are equal in terms of runtime

Small sample from end of test execution

```bash
[01] ✔ in 4354ms
[04] ✔ in 4794ms
[02] ✔ in 3328ms
[04] ✔ in 7131ms
[03] ✔ in 13437ms
[01] ✔ in 11558ms
[05] ✔ in 21881ms
[02] ✔ in 7051ms
[02] ✔ in 4259ms
[03] ✔ in 15055ms
[02] ✔ in 5372ms
[03] ✔ in 5274ms
[03] ✔ in 17304ms
```

If all tests in thread 1 would complete in 2 minutes, then thread 1 would not pick up any more tests even if thread 2 - 5 have 6 tests all still waiting in their queue. This means that tests are only as fast as the slowest thread rather than allowing tests to be picked up by an idle thread.

In the example above thread 02 and 03 were slower than others. thread 01, 04 and 05 were waiting in idle while 02 and 03 were continuing with their queue.

In an ideal world, thread 01, 04 or 05 would see this incomplete queue and pick up a task to speed up test performance.

### Details

* CodeceptJS version: 3.5.3
* NodeJS Version: 18
* Operating System: MacOS / Linux
* puppeteer

Contributor guide

Open the contributing guide

Assessment

This issue has not been assessed yet.

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.