[nightly] Limit many drivers iteration to 4000 iterations

[fishbone]

Why are these changes needed?

Due to faster running of many drivers, we limit the iteration to 4k for the test.

Related issue number

Checks

• I've run scripts/format.sh to lint the changes in this PR.
• I've included any doc changes needed for https://docs.ray.io/en/master/.
• I've made sure the tests are passing. Note that there might be a few flaky tests, see the recent failures at https://flakey-tests.ray.io/
• Testing Strategy
  • Unit tests
  • Release tests
  • This PR is not tested :(

[rkooo567]

is this a temporary solution? Or is the memory leak identified, and it is unsolveable?

[bveeramani]

‼️ ACTION REQUIRED ‼️

We've switched our code formatter from YAPF to Black (see #21311).

To prevent issues with merging your code, here's what you'll need to do:

1. Install Black

pip install -I black==21.12b0

2. Format changed files with Black

curl -o format-changed.sh https://gist.githubusercontent.com/bveeramani/42ef0e9e387b755a8a735b084af976f2/raw/7631276790765d555c423b8db2b679fd957b984a/format-changed.sh
chmod +x ./format-changed.sh
./format-changed.sh
rm format-changed.sh

3. Commit your changes.

git add --all
git commit -m "Format Python code with Black"

4. Merge master into your branch.

git pull upstream master

5. Resolve merge conflicts (if necessary).

After running these steps, you'll have the updated format.sh.

[fishbone]

@rkooo567 yes, it is. I'll create another ticket to track the long-term updates.

[fishbone]

@rkooo567 I created the issue here #22027
Should the dashboard be put into core backlog?

[rkooo567]

Hmm I think we should probably track it for now and pass it to other teams once there's a clear owner for the dashboard?

I think removing memory leak should be a critical requirement for the ray core.