PBM-1490-Documented the ability to set file size limit for large backups

[nastena1606]

modified: docs/details/storage-configuration.md
new file: docs/features/split-merge-backup.md
modified: mkdocs-base.yml
modified: docs/reference/configuration-options.md

[Copilot]

Pull Request Overview

This PR documents the ability to set file size limits for large backups in Percona Backup for MongoDB (PBM). The documentation explains how PBM can split large backup files into smaller pieces when they exceed configured size limits.

• Adds documentation for the maxObjSizeGB configuration parameter across all supported storage types
• Creates a new feature documentation page explaining the split-merge backup functionality
• Updates navigation to include the new documentation page

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
mkdocs-base.yml	Adds navigation entry for the new split-merge backup documentation
docs/reference/configuration-options.md	Documents the maxObjSizeGB parameter for S3, GCS, filesystem, and Azure storage types
docs/features/split-merge-backup.md	New comprehensive documentation explaining how large backup file management works
docs/details/storage-configuration.md	Minor grammar fix in existing content

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[Copilot]

The maxObjSizeGB parameter appears under the filesystem storage section but should be at the same indentation level as filesystem to be a sibling of the storage type configuration, not nested within it.

[boris-ilijic]

We need to change type int->float64. The other comments are optional.

[boris-ilijic]

Eventually, a backup file (typically collection or index) ....

[nastena1606]

Reworded

[boris-ilijic]

float64

[boris-ilijic]

float64

[boris-ilijic]

float64

[boris-ilijic]

float64

[boris-ilijic]

My recommendation is to add warning something like this:

We don't recommend modifying the maxObjSizeGB param. The default value is sufficient for most use cases, and setting it to a lower value can be dangerous as it may cause a single backup file to be split into a large number of smaller files.

[nastena1606]

But what is the implication, does it affect performance or PBM won't be able to merge all those chunks together?

[boris-ilijic]

Yes, mostly performance degradation. Also on the storage it'll be large number of files instead of single file of few of them, so it'll be harder to manage those (e.g. copy or browse), but I wouldn't mention that details.