Improve chunk upload AssemblyStream performance

[PVince81]

Description

The assembly stream's steam_read method is usually called for every 8192 bytes by PHP.
In the current code, it would call fopen() on the chunk's node in every call, which means for every 8k bytes, which is very unefficient.

This fix caches the stream until the end is reached before resolving the next node.

Related Issue

Partial fix for #25493

Motivation and Context

Chunk assembly is too slow in the new endpoint!

How Has This Been Tested?

Check out this other PR #25494 which contains the fix as well.
Upload a big file of around 60+ MB in the web UI in a subfolder.
Check the network console for the final "MOVE" of ".file".

Before: 20440ms
After: 600ms

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

Backports:

• stable9.1 ?

Please review @DeepDiver1975 @owncloud/filesystem

[mention-bot]

@PVince81, thanks for your PR! By analyzing the annotation information on this pull request, we identified @DeepDiver1975, @LukasReschke and @nickvergessen to be potential reviewers

[guruz]

👍

[DeepDiver1975]

👍

[PVince81]

stable9.1: #26072

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.