Wednesday, August 15, 2007

Team System 2008

Brian (VSTS Product Group Manager) in his recent post published the TFS 2008 feature list. I am very happy to see some of the features specially support for SPS 2007 and SQL reporting on any server.
My organization already deployed a SPS 2007 and SQL Reporting 2005 server farms in addition to the SQL Server 2005 farm hosting our data marts and RDBMS databases. TFS 2008 will enable us to leverage the existing infrastructure rather than build all the infrastructure from scratch. The cost of deploying/maintaining TFS 2008 will be much less than setting up a dedicated high availability environment.
The only thing I am still looking for answers is the support for 64 bit OS in TFS 2008. Unfortunately the TFS 2005 middle tier was not supported on 64 bit OS. I hope TFS 2008 will be supported on a 64 bit environment. I will try to install it on a virtual machine and see if that works.

Boxing/UnBoxing Continued

Since my last post I ran across some new questions.
1. Does boxing have a performance issue or UnBoxing?
2. In case when an int has to be concatenated with string is it better to use ToString() method.

After running some tests I have concluded.
Boxing is slower than UnBoxing and ToString() is slower than boxing. So if one cannot avoid boxing do not try to use ToString() methods they seem to be slower.

My current challenge is that I have a Winform screen with 15 drop downs and 6 grids. In order to bind the the controls I am converting strongly typed Business entities to DataTables. There are quite a few properties in the business entities which are int and DateTime resulting in boxing and impacting the performance of the screens.

Hopefully I will come up with a solution to this issue soon.

Wednesday, August 08, 2007


Its been nearly three years since I last blogged and what better topic to start blogging back again than boxing/unboxing.
Most of the literature that I can find online tells me what is a boxing/unboxing operation or what are its disadvantages but none could definitively answer to the question that came up during a recent code review. Whether this code causes boxing/unboxing
class Class1
int i = 10;
static void Main(string[] args)
Class1 x = new Class1();
int a = x.i; //unboxing??
x.i= 20; //boxing??
I myself when initially came across the concept of boxing/unboxing used to think that the above code will cause box and unbox operations to be called but that's not the case. The above code does not cause boxing/unboxing.
The idea of boxing unboxing is a little little difficult to grasp and I have found lots of people(including myself) struggling with it. There is an article on type fundamentals by Jeffrey Richter which may help explain things and also there is a blog post by David Cumps which gives a nice visual explanation of boxing/unboxing
To figure out in the C# code if it has any box operation look for the following
  1. An instance of a value type is assigned to a variable/field/property of the type object
  2. An instance of a value type is cast to an instance of an object type
  3. An instance of a value type is passed to a method/property indexer which has object type as a parameter.
To figure out in C# code if it has any Unbox operation check whether an instance of a type object is being cast to an instance of a value type.
Below are the few common cases of boxing and unboxing
int j;
int i = 10; // can be any value type like float, double, Point, DateTime, structures etc.
//The standard example
object o = i; //implicit boxing
o = (object)i; //explicit boxing
j = (int)o; //unboxing
//String.Format and its variations
string.Format("Boxing {0}",i); //implicit boxing
Console.WriteLine("Boxing {0}",i);
StringBuilder strBuild = new StringBuilder();
strBuild.AppendFormat("Boxing {0}",i); //implicit boxing
ArrayList list = new ArrayList();
list.Add(i); //implicit boxing
list.BinarySearch(i); //implicit boxing
list.IndexOf(i); //implicit boxing
list.Insert(2,i); //implicit boxing (only for i)
list.LastIndexOf(i); //implicit boxing
list.Remove(i); //implicit boxing
j = (int) list[0]; //unboxing
Hashtable coll = new Hashtable();
coll.Add(i,i); //implicit boxing(twice)
coll.Contains(i); //implicit boxing
coll.ContainsKey(i); //implicit boxing
coll.ContainsValue(i); //implicit boxing
coll.Remove(i); //implicit boxing
j = (int) coll[i]; //implicit boxing for indexer and unboxing for assignment
DataTable dt = new DataTable();
DataRow dr = dt.NewRow();
dr["UntypedColumn"] = i; //implicit boxing
dr["IntColumn"] = i; //implicit boxing
j = (int) dr["UntypedColumn"]; //unboxing
j = (int) dr["UntypedColumn"]; //unboxing