Enterprise Library Test Guide - Willy .Net

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Enterprise Library Test Guide
Results showed that, for the tests that used 20 KB values, the 32-bit computer started
paging because there was insufficient memory to hold all the data. The Pages/Sec
performance counter went up between 160 pages/sec and 170 pages/sec. The % Processor
Time performance counter fell far below capacity. Generally, it was no higher
than 34 percent. The Private Bytes performance counter for the ASP.NET w3wp.exe
worker process was close to 1.7 GB.
For the 64-bit computer, it was possible to use values that were as large as 30 KB
while still maintaining acceptable levels for both response times and transactions per
second. During the heaviest load, the Private Bytes performance counter was at approximately
5 GB. There was little contention. The CLR contention rate/sec indicated
values less than 8 and the Pages/sec performance counter was zero.
Measuring Initialization Costs
The initialization cost is the amount of system resources and time necessary to prepare
an application block so that it can begin to execute requests. Subsequent costs
will be much less because the necessary code and data structures are now cached.
This measurement is not relevant for Web applications because the first hit (the
initialization process) is not considered an important factor in terms of performance.
However, the measurement does matter for smart client applications because clients
frequently stop and restart the application. This means that clients will repeatedly
initialize the code variables and data structures.
The .NET Framework XmlSerializer class, which Enterprise Library uses, illustrates
this. The initialization cost is high because the class must be compiled. Afterward, the
compiled version is in the cache.
For situations where the initialization cost is important, you should measure the
times it takes to execute the most expensive execution paths. To do this, write a test
console application that measures and displays the initialization costs. The following
code shows how to do this for the XmlSerializer class.
public class OrderedItem
{
public string Nationality;
public string Description;
public decimal UnitPrice;
public int Quantity;
}
class Class1
{
[STAThread]
static void Main(string[] args)
{
for(int i=0;i