Microsoft has resolved a bug that made OneDrive and OneDrive for Business slow on Linux machines but not on any other platform, including iOS, Chrome OS, macOS, and Windows.
A Microsoft OneDrive spokesman called Edgar has now confirmed that the issue has been resolved, pointing to a failure in a browser component designed to speed up background processing called prefetching.
"We identified that StaticLoad.aspx, a page that prefetches resources in the background for Office online apps was using the link prefetching browser mechanism only for certain platforms, iOS, Chrome OS, Mac, Windows, but for Linux it was falling back to a less efficient technique that was causing the issue. Rest assured that this was not intentional. It was an oversight," Edgar said on Hacker News.
Microsoft fixed the issue by disabling prefetching and then enabled it again after updating StaticLoad.aspc for Linux.
"We apologize for the inconvenience this may have caused," he added.
Linux users have been putting up with the inconvenience since at least November when, according to Redmond Magazine, an Ubuntu user complained of OneDrive sluggishness on Microsoft's forum. It notes there were suspicions that Microsoft was doing browser sniffing and perhaps penalizing OneDrive Linux users.
Linux users have been expressing their pleasure at hearing from a Microsoft employee that the issue was caused by an oversight and not an intentional punishment aimed at them.
Those original suspicions may have been misplaced for other reasons. Under CEO Satya Nadella's push for cross-platform software to power its cloud business, Microsoft has disavowed its old war on Linux and now embraces open-source software, which former Microsoft CEO Steve Ballmer once described as a cancer.
"This was not intentional," Edgar emphasized of the Linux-specific OneDrive bug.
Edgar explains that it needed to detect the browser being used because not every browser supports prefetching. While a technique it used worked with Safari on Mac, it hung for Chrome on Linux.
"The second technique does not hang on Safari on Mac, but it does on Chrome on Linux. We will definitely ensure that more Linux testing is done. Our goal in OneDrive is to build a service that enables as many people as possible to be productive, so if in cases it looks like we are trying to favor our own OS, that is not really our intention," wrote Edgar.