data store mgr: Increase the max number of workflows to 100

[oliver-sanders]

• Workaround for artificial workflow limit #569

Easy way to test:

• Launch a bunch of workflows.
• Run cylc pause '*'.
• The workflows that are being updated will change state to paused, the ones which aren't will stay as running.

Try adjusting the max_threads value to a lower number.

Check List

• I have read CONTRIBUTING.md and added my name as a Code Contributor.
• Contains logically grouped changes (else tidy your branch by rebase).
• Does not contain off-topic changes (use other PRs for other changes).
• Applied any dependency changes to both setup.cfg (and conda-environment.yml if present).
• Tests are included (or explain why tests are not needed).
• CHANGES.md entry included if this is a change that can affect users
• Cylc-Doc pull request opened if required at cylc/cylc-doc/pull/XXXX.
• If this is a bug fix, PR should be raised against the relevant ?.?.x branch.

[wxtim]

On a practical basis this seems to work, though very unperformant on my Intel® Core™ i5-2520M CPU @ 2.50GHz × 4

The ghosting of the icons with state stopped when they are actually playing in the workflow sidebar is something which is happening before and after this change. Is that a known issue?

[wxtim]

• Read code
• Tried change

[oliver-sanders]

Is that a known issue?

Look at your UIS logs, you should see attempts to connect to the workflows there, if there were issues connecting they should be logged too.

[MetRonnie]

On a practical basis this seems to work, though very unperformant on my Intel® Core™ i5-2520M CPU @ 2.50GHz × 4

(It's easier to test with workflows running on the Cylc servers)

[MetRonnie]

Tested. Reproduced the 8-workflow limit on master/1.4.x and not able to reproduce on this branch