Bug 164913 - Calc opens very slowly if all cells of a column are merged
Summary: Calc opens very slowly if all cells of a column are merged
Status: NEW
Alias: None
Product: LibreOffice
Classification: Unclassified
Component: Calc (show other bugs)
Version:
(earliest affected)
24.8.4.2 release
Hardware: x86-64 (AMD64) Windows (All)
: medium normal
Assignee: Not Assigned
URL:
Whiteboard:
Keywords: perf
Depends on:
Blocks: File-Opening
  Show dependency tree / graph
 
Reported: 2025-01-29 07:16 UTC by ckakman
Modified: 2025-01-29 13:42 UTC (History)
1 user (show)

See Also:
Crash report or crash signature:

Attachments
An empty sheet with a single merged column (675.82 KB, application/vnd.oasis.opendocument.spreadsheet)
2025-01-29 07:17 UTC, ckakman 		Details
View All Add an attachment (proposed patch, testcase, etc.)

Note You need to log in before you can comment on or make changes to this bug.
Description ckakman 2025-01-29 07:16:10 UTC 
Description:
The title says it all.

I merged all cells of a column by selecting a column and clicking the merge button in the toolbar. Opening a Calc file with such a merged column is very, say 10x, slow.

Steps to Reproduce:
1. Select a column in Calc
2. Merge all cells of the selected column
3. Save in ODS format and reopen the file

Actual Results:
Very slow to open

Expected Results:
File opens in a couple of seconds.


Reproducible: Always


User Profile Reset: No

Additional Info:
I haven't tried on any platform other than Windows 10 and with Excel file formats.
Comment 1 ckakman 2025-01-29 07:17:11 UTC 
Created attachment 198843 [details]
An empty sheet with a single merged column
Comment 2 m_a_riosv 2025-01-29 11:21:49 UTC 
Yet slow, but quicker with
Version: 25.8.0.0.alpha0+ (X86_64) / LibreOffice Community
Build ID: a8ec21adf255b70bb6eeb0a1717190df303d8b26
CPU threads: 16; OS: Windows 11 X86_64 (build 26100); UI render: Skia/Vulkan; VCL: win
Locale: es-ES (es_ES); UI: en-US
Calc: CL threaded

It is a bit quicker opening with Excel.

Seems like a corner case.