Parse-server: Enable direct access by default

[mtrezza]

Is your feature request related to a problem? Please describe.

• Direct access of Parse Server within Cloud Code is feature flagged for some time.
• It is used in production environments by some without feedback of any major issues.
• Given the potential for significant performance improvement for Parse Server deployments without any code changes necessary, it would be beneficial to move it out of its experimental state and enable it by default.

Describe the solution you'd like
Identify any issues, remove the feature flag, maybe enable by default, see https://github.com/parse-community/parse-server/issues/6637#issuecomment-636330194.

Additional context

• Continuation of https://github.com/parse-community/parse-server/issues/5442
• Direct access was merged feature flagged in https://github.com/parse-community/parse-server/pull/5550

Related PRs

• [ ] https://github.com/parse-community/parse-server/pull/6636

Related discussions

• https://github.com/parse-community/parse-server/issues/4658

[mtrezza]

As quick performance test for directAccess here is a load test for a _User query by objectId:

| response time | status quo | direct access |
|---------------|------------|---------------|
| avg. | 193.02ms | 64.69ms |
| min | 9ms | 9ms |
| p95 | 459ms | 279ms |
| p99 | 611ms | 427ms |

This shows that it's well worth pursuing this feature.

[dplewis]

Check out https://github.com/parse-community/parse-server/pull/6636#issuecomment-618121110

[mtrezza]

In a previous series of load testing, we realized that JSON serialization of large objects was a large source of CPU consumption, and was inducing latency in the responses as serialization is blocking the node process.

In our case, we decided not to go with the direct access but to let internal cloud code calls reach another server, as it was the most optimal solution for our workload

This means that enabling directAccess by default can be a breaking change as described in #4658 (comment), so maybe it should be disabled by default?

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[mtrezza]

Closed by https://github.com/parse-community/parse-server/pull/6636