Visual Studio Team Services having some 'performance issues'

Microsoft has said it suspects a code change has caused "performance issues" for its cloud-based code repository and dev collaboration platform, Visual Studio Team Services.

At 7:21 UTC this morning, Redmond's team members noted on the status page that "a potentially customer impacting alert" was "being investigated" for the service.

At 8:15 UTC, they noted "high processor time on all web tiers" had led to "slow calls to our central Shared Platform Service".

Which means... well, slowness for many users. And they took to Twitter to complain, as you'd expect.

We can't even do a standup/scrum meeting this morning because VSTS workboard is so slow :(

— styfle (@styfle) 10 October 2017

Visual Studio Team Services program manager Martin Woodward acknowledged that customers were affected on Twitter.

Apologies - I'm on the call now. We're currently working on performance issues. Updates soon - https://t.co/iB6UL5Ta3o

— Martin Woodward (@martinwoodward) 10 October 2017

After sifting through traces and memory dumps, at 12:12 UTC the team said: "Our working theory is that the high CPU consumption on the Shared Platform Service web roles is due to a code change that introduced a regular expression in one of the underlying libraries that our product took a dependency on."

The team said it was working to fix the relevant library and "scaling out the web roles in Shared Platform Service", but said there was no ETA for when it would be fixed.

Visual Studio Team Services went offline for five hours last year.

We have asked Microsoft for comment. ®