johnc johnc - 6 days ago 6
C# Question

Very slow compile times on Visual Studio 2005

We are getting very slow compile times, which can take upwards of 20+ minutes on dual core 2GHz, 2G Ram machines.

A lot of this is due to the size of our solution which has grown to 70+ projects, as well as VSS which is a bottle neck in itself when you have a lot of files. (swapping out VSS is not an option unfortunately, so I don't want this to descend into a VSS bash)

We are looking at merging projects. We are also looking at having multiple solutions to achieve greater separation of concerns and quicker compile times for each element of the application. This I can see will become a DLL hell as we try to keep things in synch.

I am interested to know how other teams have dealt with this scaling issue, what do you do when your code base reaches a critical mass that you are wasting half the day watching the status bar deliver compile messages.

I neglected to mention this is a C# solution. Thanks for all the C++ suggestions, but it's been a few years since I've had to worry about headers.


Nice suggestions that have helped so far (not saying there aren't other nice suggestions below, just what has helped)

  • New 3GHz laptop - the power of lost utilization works wonders when whinging to management
  • Disable Anti Virus during compile
  • 'Disconnecting' from VSS (actually the network) during compile - I may get us to remove VS-VSS integration altogether and stick to using the VSS UI

Still not rip-snorting through a compile, but every bit helps.

Orion did mention in a comment that generics may have a play also. From my tests there does appear to be a minimal performance hit, but not high enough to sure - compile times can be inconsistent due to disc activity. Due to time limitations, my tests didn't include as many Generics, or as much code, as would appear in live system, so that may accumulate. I wouldn't avoid using generics where they are supposed to be used, just for compile time performance


We are testing the practice of building new areas of the application in new solutions, importing in the latest dlls as required, them integrating them into the larger solution when we are happy with them.

We may also do them same to existing code by creating temporary solutions that just encapsulate the areas we need to work on, and throwing them away after reintegrating the code. We need to weigh up the time it will take to reintegrate this code against the time we gain by not having Rip Van Winkle like experiences with rapid recompiling during development.


The team listed several options for accelerating the build (at this point about half-way down the page):

In decreasing order of speedup:

  • Install Microsoft hotfix 935225.
  • Install Microsoft hotfix 947315.
  • Use a true multicore processor (ie. an Intel Core Duo 2; not a Pentium 4 HT).
  • Use 3 parallel builds. In Visual Studio 2005, you will find the option in Tools > Options... > Projects and Solutions > Build and Run > maximum number of parallel project builds.
  • Disable your anti-virus software for .ilk, .pdb, .cc, .h files and only check for viruses on modify. Disable scanning the directory where your sources reside. Don't do anything stupid.
  • Store and build the Chromium code on a second hard drive. It won't really speed up the build but at least your computer will stay responsive when you do gclient sync or a build.
  • Defragment your hard drive regularly.
  • Disable virtual memory.