What you’re seeing is a known situation with some Personal Environments: a very small amount of your own work, but a very large amount of System Data due to:

• Pre‑installed system apps (LifeTime, Users, System Components, App Feedback, etc.)
• Multiple tagged / retained versions of those system modules that cannot be deleted from Service Center

Since you’ve only used the environment for ~6 days and have a single small app, the numbers you report (≈2.6 GB System Data, 130 excluded module versions) almost certainly come from those tagged system module versions, not from your BookMngmt app.

1. Why System Data is so high in a “new” Personal Environment

Personal Environments have a fixed 2 GB DB limit. System Data includes:

• Platform metadata (module definitions, app versions, configurations)
• Logs
• Forge components (if any)
• All module versions (each publish increases System Data) Manage the database space of your personal environment

When OutSystems upgrades or maintains Personal Environments, it can leave multiple module versions for core apps tagged in LifeTime/solutions. These versions:

• Appear in Service Center’s “Delete Old Module Versions” screen as excluded (your 130 versions)
• Cannot be deleted by you because they belong to tagged applications/solutions and/or are considered system versions Database full, Cant delete system data, Included DBCleaner Table records info, Help!

So yes: the retained tagged system module versions are very likely responsible for most of your 2.6 GB System Data.

2. Why you can’t clean it yourself

You already checked:

• Service Center → Factory → Modules → “Delete Old Module Versions” → no deletable versions
• Message: “130 Module versions are excluded from this list because they are used in tagged versions of applications or solutions.”

Those excluded versions:

• Belong to system/standard apps (LifeTime, System Components, Users, App Feedback, etc.)
• Are referenced by tagged application versions or platform solutions
• Are intentionally protected from deletion through the UI Database full, Cant delete system data, Included DBCleaner Table records info, Help!

Forge tools like DB Cleaner / DB Cleaner on Steroids / OneClickCleanup can help remove your own old module versions and deleted entities, but they cannot safely remove those tagged system versions in a cloud Personal Environment. Even if they show up, deleting them would risk breaking the environment.

3. What needs to happen (and by whom)

For Personal Environments that:

• Reach or exceed the 2 GB limit mainly due to System Data
• Have no user‑deletable module versions in Service Center

the recommended action is:

Open a Support Case with OutSystems. Support can:

• Unblock the environment
• Run internal cleanup routines on system data
• Remove or compress old tagged system versions that you cannot touch yourself
• Validate that nothing critical is removed Manage the database space of your personal environment [[After updating to Version 11.7.3 (Build 5968), Database Usage of Systems Data is 100%<>https://www.outsystems.com/tk/redirect?g=1cce0408-ea1a-4fac-9ed2-fb216a25aec9]]

In fact, the documentation for Personal Environments explicitly states:

If the personal environment becomes unavailable or usage reaches 100%, it will be necessary to open a Support Case with OutSystems to unblock the environment and suggest specific cleanup actions. Manage the database space of your personal environment

4. How to frame your request to Support

In your Support Case, I suggest you include (you already have most of this):

• Environment URL / name
• Exact usage numbers:
  • Total: 2763 MB / 2 GB (135%)
  • System Data: 2656 MB (129%)
  • Application Data: 106 MB (5%)
• Note that:
  • The environment is only ~6 days old
  • You have one small custom app (BookMngmt) with one module, one entity, two records
  • Service Center → Delete Old Module Versions shows no deletable versions
  • Message: “130 Module versions are excluded from this list because they are used in tagged versions of applications or solutions.”
• Request:
  1. Investigation and cleanup/unblock of System Data for this Personal Environment
  2. Confirmation that the retained tagged system versions are responsible for the excess usage
  3. Execution of any internal cleanup (e.g., removing obsolete tagged system versions) that is safe and supported for cloud Personal Environments

This is precisely the kind of case where OutSystems Support needs to act; you’ve already done the right checks on your side.

5. What you can do meanwhile

There’s not much you can do about the system modules themselves, but you can:

• Keep your own modules small (avoid big bootstrapped files/resources in a single module) Why is Personal Environment Database Space Management for New Developers so confusing
• Avoid installing unnecessary Forge components
• If you ever see your own modules shown in “Delete Old Module Versions”, clean those older versions promptly

But for the current situation, the system data is clearly the main problem, and only Support can address it in a Personal Environment.

Direct answer to your two final points:

1. “Could you please investigate why a newly provisioned Personal Environment already contains ~2.6 GB of System Data, and perform the necessary cleanup/unblock?”
   Investigation and cleanup/unblock must be performed by OutSystems Support, not via Service Studio/Service Center alone. Please open a Support Case and include the details you shared.

2. “Please also confirm whether the retained tagged system versions are responsible for the excessive System Data usage.”
   Based on the numbers and the “130 module versions excluded due to tagged applications/solutions” message, yes, those retained tagged system module versions are almost certainly responsible for most of the excessive System Data usage.