Oxygen very slow with large XML files

[pandrhola]

Hi, I often work with big XML files, and Oxygen gets really slow or freezes when I try to validate, search, or format them. Has anyone found a good way to make it faster?

[tavy]

Working with very large XML files can strain certain features. Here are proven ways to improve performance and stability in Oxygen when editing, validating, searching, or formatting big documents:

Quick setup
- Use the latest Oxygen version/build and 64-bit edition.
- Increase Java heap size for Oxygen (e.g., -Xmx4g if RAM allows). Make sure you edit the correct launcher (vmoptions or bat/sh for your distribution).

Editing and navigation
- Prefer Text mode for very large files; Author mode renders more and can be slower.
- Temporarily disable heavy background features for large files:
- Automatic validation as you type.
- Content completion and occurrences highlighting.
- Spell checking.
- Code folding and continuous outline sync.
- Close nonessential views (Outline, Results) and reduce the number of open editors.

Validation and schema access
- Use local XML Catalogs to eliminate network lookups for schemas/DTDs.

Formatting and structure
- Pretty-printing huge or single-line XML can be expensive. Format once, then avoid re-formatting the entire file repeatedly. If you only need part, format just the selection.

Search and XPath
- Use literal search or carefully scoped regex; avoid “highlight all matches” on massive files.
- XPath on very large files can be slower than running a focused XSLT; limit queries or run transformations instead when practical.

Very large or monolithic files
- Consider splitting into smaller modules and referencing them (XInclude or external entities), so you edit manageable pieces while producing the same combined result.
- For files that are only for inspection, use the Large File Viewer.

Environment tips
- If you’re using the Eclipse plugin, remember its heap is shared with Eclipse and other plugins; try the standalone edition or increase Eclipse’s heap.

If performance is still an issue, please share a few details so we can tailor exact steps:
- Oxygen edition and version/build (Help > About).
- OS and RAM.
- File size and whether a DTD/schema is associated (and how).
- Current -Xmx value.
- Which operation is slow (validate, search, format) and whether you run it on the whole file or a selection.

If you can provide an anonymized sample that reproduces the slowdown, we can profile it and recommend precise settings.