[ARROW-15796] [Python] Pickling ParquetFileFragment shouldn't fetch metadata

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 8.0.0
• Component/s: Python
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/31238
• Assignee: saloni jain
• Reporter: David Li
• Created: 28/Feb/22 13:05
• Updated: 11/Jan/23 11:39
• Resolved: 29/Apr/22 16:13

Description

Follow-on to ARROW-15781/https://github.com/apache/arrow/issues/12501

Pickling a ParquetFileFragment fetches metadata; we should omit the metadata if it's not already present, since fetching it can incur potentially expensive I/O.

Issue Links

• relates to: ARROW-15781 [Python] ParquetFileFragment.ensure_complete_metadata doesn't release the GIL
• links to: GitHub Pull Request #12909