Reuse RID of deleted records

[lvca]

ArcadeDB does not reuse the assigned RIDs. Never. Even when the record is deleted. This has the advantage to determine if a link is broken (the RID points to a non-existent record), useful in case of unidirectional edges.

In other cases reusing the RIDs allows reusing all the space in pages. In some use cases which are heavily based on deletes, this feature can save a lot of space and improve overall performance.

I'd like to let this configurable, so the user can decide per bucket/type, if the RIDs are reusable.

[vic0824]

Are the pages never compacted, like it happens for the indexes? If they aren't, then I agree it's useful to re-use the RIDs to optimize the space usage in pages.

[jtsmedley]

Maybe add to the check database command suggestion of RECLAIM as a flag.

[ansarizafar]

My use case is heavily based on deletes so a solution is definitely required.

[ansarizafar]

Is there any new update?

[lvca]

We have a branch where we're able to reuse the RIDs, but this decreases the insertion speed when you have a lot of records in the buckets. We're testing a better approach where we save the deleted RIDs in a separate structure. It should be out on the January release.

[ansarizafar]

It means we will be able to reclaim the space of deleted records. If I start using Arcadedb now, then would it be possible to upgrade my database to the new release?

[lvca]

Yes, it will recycle 100% of the deleted space. Upgrade will be compatible, just update the jars

[ansarizafar]

Awesome. It's a deal-breaker for my use case.

[ansarizafar]

I am still waiting for this feature.

[lvca]

We made good progress (it's in the delete-reuse-space branch), but it's still not stable enough to be merged into the main branch.