Tuesday 23 September 2014

Hitting the limit on a Local Workspace

Everybody remember the introduction of the local workspaces in 2012, enabling offline scenarios with Team Foundation Server. But did you know they have a limit on the number of files prior to performance degradation?

This limit is 100000 elements.

TF401190: The local workspace temp_WS;User has 248536 items in it,
which exceeds the recommended limit of 100000 items. To improve
performance, either reduce the number of items in the workspace,
or convert the workspace to a server workspace.

There it is. It’s not a bug, but it is a design choice by the Team Foundation Server team.

Local workspaces work leveraging the content of the hidden $tf folder, which tracks all the changes for a file (deltas) from check-out to check-in. That’s how you get features like Candidate Changes. The side effect is that despite the source copy is compressed, it is still a copy, hence you have a physically bigger workspace.

The workarounds in this case is to use a server workspace (easy) or to split the huge, monolithic workspace into several smaller workspace so you won’t hit the issue. This could be harder than just using a server workspace, but with a bit of planning it is absolutely feasible.

This post by Philip Kelley is extremely enlightening, as it is a deep comparison between local and server workspaces. Right there he explains the differences, and how they are implemented (the PendChange permission, the +R bit, etc.).

Saturday 20 September 2014

Application Insights: what’s going on?

I guess it has been a little overlooked, but there is a lot of moving around Application Insights…
The biggest thing is that with Visual Studio 2013 Update 3, Application Insights is moving towards version 2.0. It’s not a mere version change…
Application Insights is being moved to Microsoft Azure, and 2.0 is the first version of it. The move is not complete yet, so the 1.3.2 version – running on Visual Studio Online – works, and it contains all the current feature set, but bear in mind that they are “rebuilding it from the ground up as part of Microsoft Azure”.
If you want to understand which version you are running, just check the ApplicationInsights.config file: if it contains a schemaVersion, then you are using the 2.0 release.
The Azure version lacks several features at the moment (Windows Store and Windows Phone apps monitoring, different APIs) and there are a couple of architectural changes, most notably the agent-free performance monitoring.
But it does not mean you are losing anything: it was in preview on VSO, it is in preview on Azure, and you can use both. If your application or service is configured to send data to the 1.3.2 version, this is not changing as there is no automatic upgrade.
There is only one thing to consider: if you remove the 2.0 package and you restore the 1.3.2 one, you cannot return to the 2.0 without repairing the Visual Studio installation.

Thursday 11 September 2014

Again, again and again on the backups

This is a topic which I find coming back every now and then: backups of the Team Foundation Server.

Team Foundation Server is a SQL Server-based product – hence most of the backups’ work happens there. Full, Copy Only, Differential, Transaction Log: choose your flavour, as long as you are confident it’s good.

IMHO it is a good practice to keep things simple: a daily Full Backup with hourly Transaction Logs Backups provide a good level of protection without involving the (IMHO) complicated Differential Backups.

If you can, use the OOB tool: it is mature enough to do its job without too many worries. But if you happen to need a manual backup, there are a couple of information to keep in mind…

In order to be supported by the Microsoft CSS your backups must be synchronized – no exceptions. The safest way of doing that, as it required manual interaction with the TFS databases, is to follow this MSDN walkthrough. I introduced a slight modification as I manage a big deployment which uses SQL Server AlwaysOn, which is just the verification of the preferred backup instance, but the core steps are the same.

The reason behind that is pretty simple: the Team Project Collection databases refer to objects (like IDs, or identities) stored in the TFS_Configuration database. If you restore a Team Project Collection database which contains something not aligned with the Configuration DB, it is going to end badly…

And remember to test the restore – otherwise you do not have a backup Smile