Collabora Online performance wins – what we did for CODE and Collabora Online 21.11

Learn about the many performance improvements in CODE and Collabora Online 21.11

CODE 21.11 – announced yesterday – and of course also Collabora Online 21.11 bring together many performance improvements that we have been working on through the 6.4.x lifecycle as well as some more advanced optimizations. These are rather hard to screenshot for your viewing pleasure for obvious reasons, so please forgive some technical details and links to further reading for those interested. It is ongoing work; more about that at the end of this blog.

Asynchronous save

Collabora Online works hard to preserve your edits in the unlikely case of server-side failure. We regularly auto-save the document while users are editing, however in the past storing your document through to the back end storage had to be completed successfully before the user could continue typing. This could cause some jerkiness from time to time as people typed. Now this up-loading part of the saving is done asynchronously – i.e. in the background. For more technical details you can enjoy a talk on the design. For times when it is necessary to save synchronously such as during a save-as, we now provide animated user-feedback, color-coded according to the respective current application:

Accelerated JavaScript

Lots of work has been done first to profile, and then to optimize the performance of Collabora Online. Our profiles showed, somewhat surprisingly, that a lot of the scope for improvement was in the browser. As such we have significantly improved our websocket message handling, pixel processing and grouping of UI refreshes to give very significant interactivity improvements to more recent 6.4.x versions.

Online calc profile image before optimization
avoiding duplicate work (shown) by performing DOM updates after processing a batch of incoming events.

Moving more of the document to the client

Collabora Online 21.11 brings an understanding of text documents’ page positioning to the browser. That allows us to rendering page surrounds there avoiding a source of perceived flicker when moving up and down documents, and giving a smoother experience. This builds on more recent work in Calc to render worksheet backgrounds, and grid in the browser for similar reasons – giving slicker editing.

Improved spreadsheet performance in Calc

Collabora continues to put a lot of effort into enhancing the performance of our collaborative office suite. As an example, our streamlining of the Find & Replace functionality resulted in a massive performance boost. Also, opening speed of large XLSX files saw a some significant improvements. In Collabora Online 21.11, we have fundamentally revised the way spell checking is done in Calc with a new spell check that prevents continual re-rendering as strings are processed, while also caching spell-checking information, yielding considerable performance improvements. Similarly, AutoFilter searching has been optimized for large numbers of unique records.

Improved multi-user editing

One of the unfortunately pathological test-cases users like to do is to mash the keyboard – which generates text at around ten times the speed of a normal typist. Nevertheless this is something we have been optimizing along with scalability to larger numbers of concurrent editors of the same document. For more details checkout some insights into our ongoing work, or a deeply technical blog on optimizing for a larger number of users. Failing that – we have a video of a torture test of an intense multi-user editing session showing old, 6.4.x, and 21.11 versions from top to bottom:

Optimizing pathological loads – old/6.4.x/21.11

Ongoing work

We continue to work to profile and optimize uses-cases that are important to our users, the upcoming 21.11 micro-releases will exhibit more continuous improvement in this area – as well as ongoing improvements to our document pixel compression to make things even faster and lighter. It is well worth staying up-to-date with the latest releases.

There is also a summary talk of many other recent performance improvements for those with a deep interest in this area.

Test CODE 21.11

 

Please try out CODE 21.11 and let us know of any workloads which you find have issues so that we may expand our internal testing & benchmarking to include them.

About Collabora Online

Collabora Online is the powerful LibreOffice-based online office that supports all major documents, spreadsheets and presentation file formats, which can all be easily integrated in many infrastructures and solutions. Key features are collaborative editing and excellent office file formatting support. Collabora Online is excellent for enterprises that need a powerful office suite in the Cloud, or on-premises, that protects their privacy and allows them to keep full control of their sensitive corporate data. Collabora Online – built on LibreOffice Technology – enables Hosting and Cloud businesses to include document viewing and collaborative editing functionality into their service offerings.

 

 

Collabora Online performance wins – an insight into our ongoing work

Optimizing the performance of Collabora Online is one of the central focal points within our current development work. Following improvements in the recent Collabora Online 6.4.10 release, the upcoming 21.11 release will exhibit more of the continuous improvements in this area. The improvements may be noticeably experienced through a variety of daily work done by means of the software. But how exactly does the implementation of massive performance improvements work? It can be compared to solid detective work. Follow us through this search for clues!

Performance improvement for multiple users – a detective story 🔎

In advance of the actual coding, working on performance improvements closely resembles detective work. Simulating multiple users working on the same document, is something that turned out to be feasible with the feature in LibreOffice purposed for displaying a document within different windows (Window > New Window). This was a feature that already existed in LibreOffice predecessor OpenOffice. It may be a rarely used feature on the desktop, but it does mirror the way of collaborative editing with Collabora Online. However, one must then find out how this code scales… The investigator in this story is Collabora developer LuboÅ¡ Luňák. He was on to something big here, which led to significant performance improvements across various levels, ultimately benefiting all users of LibreOffice Technology. The technical details of his search and subsequent conclusions can be seen on LuboÅ¡’ blog.

 

 

Performance wins illustrated 📊

While extensive work continues with its progress, a list of current performance improvements is also available on LuboÅ¡ Luňák’s blog. The following video of the Collabora Online perf-test – a test routine we use to measure performance in Collabora Online – illustrates the performance improvements of the implementations already made. The test simulates the fast, simultaneous typing of six users in a document (the other five are not visible in the video because they are writing elsewhere in the document). The rigorous test setting, which goes far beyond what is required of the software in everyday use, is ideally suited to visualizing performance improvements. In the video, you can see the performance of Collabora Online before the latest optimizations in the upper excerpt, and the significantly better performance in current versions during (middle) and after optimizations have been implemented (bottom).

Optimizing pathological loads – before/during/after

 

Performance talk at COOL Days 2021 🆒

Collabora developer LuboÅ¡ Luňák discussed the various performance improvements in Collabora Online during the Developer Day at COOL Days 2021, a conference hosted by Collabora and dedicated entirely to Collabora Online. His talk “Rendering wastage and performance wins” covered the profiling process, described existing performance issues and displayed a variety of improvements at different levels. Technically interested people can find his talk on YouTube. The corresponding slides are also available for download.

Watch the video!
Download the slides!

 

 

Please try out Collabora Online 21.11 – RC 1, and let us know of any workloads which you find have issues so that we may expand our internal testing & benchmarking to include them.

About Collabora Online

Collabora Online is the powerful LibreOffice-based online office that supports all major documents, spreadsheets and presentation file formats, which can all be easily integrated in many infrastructures and solutions. Key features are collaborative editing and excellent office file formatting support. Collabora Online is excellent for enterprises that need a powerful office suite in the Cloud, or on-premises, that protects their privacy and allows them to keep full control of their sensitive corporate data. Collabora Online – built on LibreOffice Technology – enables Hosting and Cloud businesses to include document viewing and collaborative editing functionality into their service offerings.