Why is Calc so much slower at opening/saving files than MS-Office? (win7 x64)

Why in Calc (Spreadsheet) saving is so slow (os win7x64) ms office excel do this with it file in 10 times quickly? Open this file to slow too, than ms office excel.

Hi @Serg, There are some new 3.6 and 4.0 (beta) builds available for download. Could you please download one of those builds and let us know if you’re seeing any speed-ups in opening or saving files? Thanks!

Related question: Slow in Spreadsheet after update to

The new 4.0 is just as excruciatingly slow. I’m losing my temper. Time to consider alternatives.

@imusorka LibreOffice 4.0 is much (times) faster then 3.6. Old Apache OpenOffice 3.4.1 is much faster than even the latest LibreOffice 4.0.

Incidentally, at least in the long past history, some MS Office programs would effectively ‘coredump’ the application data’s memory contents into a file to save it, then read it back in directly into RAM when loading. LibreOffice instead translates application data to a valid, standardized format when writing it out since its beginning (I’m assuming), which adds a step.

I too experience slow loading/saving in Calc and this seems to be directly related to document size. For example, a document with 13 worksheets ranging from a few to 550 lines takes much longer to load/save than a document with fewer sheets. MS Office is lighting fast with both. I must stress that all documents are now ODS converted from XLS. My system is i7, 4GB RAM and an SSD (!) and all of this makes no difference.

@imusorka, Thanks for the detailed notes.

@imusorka (and others), @mmohrhard reports that “3.6 until 3.6.4 has a performance problem with conditional formatting, but it will be fixed in 3.6.5”. Who wants to be a beta-tester and see if the latest builds work well?

I have just replicated the lag in Has anyone tried out 4.0?

Yep, I get a serious, size-related lag under LO and Ubuntu 12.04 (32-bit). e.g., saving a 3.1 MB .xls file takes 37 seconds by my watch. Same file takes ~4 seconds when converted to .ods
Further system info: Intel dual core E7300 (2.66 GHz ea.), 3.9 GB RAM.
Anythign I can do/add to help?

@Pi – Please see my answer above: For performance issues, please file a bug and follow those steps. If the same operation on the same file used to be much faster in an older verison, that’s definitely something we want to hear about!


Thanks for the response, qubit. Based on your guidancem, I’ve filed a bug.
I haven’t done more thorough testing than this (I’m not a programmer), but I don’t think it’s faster with earlier versions; I’m getting similar performance when using either v4.2.1.1 at work (that E7300 CPU machine) and at home on a quad-core i7 with 12 GB RAM.
I do want to stress that I love LO, and am very appreciative of everyone’s fabulous work on it. Cheers!

I use 3.5, working with *.xlsx file created in ms office, but libre office 3.4.1 working not much but quickly than 3.5, but ms application working much quickly.

@Serg, Thanks for the update. If you do get a chance to try out LO 4.0 (beta builds available; it will ship in about a week), please let us know about your experience so we can try to improve Calc. Thanks!


  • fdo#51019 - EDITING: long delay after every action was fixed (reported against the 3.5 branch)

If there are ongoing performance issues, we’ll want to start filing ‘perf’ bug reports against them.

Update: Just wanted to highlight @mmohrhard’s comments:

Without the help from the community providing us with real world documents showing performance issues we have a hard time improving the performance. Please spread this word whenever you see someone complaining about the performance.

If you have reports/concerns about performance of certain documents in LibreOffice, please go straight to the bugtracker and file a bug. Please add the word “perf” to the whiteboard field of the bug report so that the developers can easily view all of the performance-related bugs in one list.


Unfortunately, extremely few users seeing performance problems will file bug reports. Why?

  1. Who’s willing to share their real-world large documents on a public bug tracker?
  2. Most users don’t open the same document with both MS Office and Libre, so they have no good comparison any more. Only users who’ve recently switched, or are in the process of switching, will have expectations of fast load times.
  3. Users of large files tend to work in them for long periods of time, so they put up with the slow load at the beginning of the day, if they’re going to spend 8 hours in the document. It’s not worth it for them to file a bug.
  4. Most users don’t realize slow loading is a “bug”, or that a bug tracker exists.
  5. Only 1% of users take the time to file bugs.

What’s the solution? I think the most realistic one would be for LO developers themselves to find their largest files and open them in MS Office to compare the speed.

You should tell us what version of LibreOffice You use. E.g. Calc 3.5 import native files (.ods) faster approximately about from 86% to 90%.

Microsoft Office always will be quickly if you save documents in Microsoft’s own format. Save document in ODS (if you have Office 2007 SP2 or newer one) and import it in Calc 3.5. If I were you I never expect that Calc would be faster ten Excel in import non native files.

I am finding the same problem, but with Writer.

I run LibreOffice on OpenSuse 12.1 X64, so I don’t think this is problem is specific to the Windows version, although it could be something to do with X64.

At first I thought it could be a problem about exporting to .doc format, as I happened to be working on a Word document. So I saved it as .odt and it still takes about 20 secs per save. I’m not sure how long it was taking before, using LibreOffice 3.4.5, but I have a habit of pressing Ctrl-S every few seconds, and it was saving seamlessly, so I’d guess no more than a couple of seconds.

It’s not a particularly large document - the odt file is only 130KiB (the doc version was 1.4 MiB). It is a single table covering about 70 pages, but there are no graphics in it.

I just tried a larger document (1.5 MiB, 59 pages with a lot of complex graphics) and saving that took over 40 secs.

Finally I tried starting a new document, typed a couple of sentences in it and saved. It took only a second or so, but if I remember rightly, previously, this would have seemed instantaneous.