Michael's Coding Den: System

Managed wrapper for GC API

Thu, 19 Apr 2007 18:43:10 GMT

We are all using the gacutil.exe to add/remove assembly to/from GAC, but in some cases gacutil can be inaccessible during installing process.

To manage this situation Microsoft provides undocumented GAC API. Unfortunately you need to use C++ for this.

But thanks to the Rory Becker it's not the issue anymore. He provides the managed wrapper for the GAC API.

Fibers and CLR

Sun, 12 Nov 2006 22:21:24 GMT

Recently I gave the note to Joe Duffy (CLR PM) that it would be really cool to know something new about Fibers in his new book about .NET Multithreading. To my pleasure Joe published a post in his blog about fibers in CLR.

The fibers are really cool thing in the unmanaged world - they are lightweighted and have the non-preemptive trait (manually scheduled). It allows to switch context fast and handle the fibers (switch, delete) on your own without diving inside of the synchronization (fiber's context can be deleted gracefully).

Unfortunately, CLR team had no time to realize fiber support in .NET. Albeit some attempts were undertaken - the idea is that managed threads and OS threads are not directly intertwined and call redirecting is possible with control of TaskManager host. But there are enough problems with fiber's handling such as: switching, affinity, debugging and etc.

More details are in the Joe's post.

Resources: 1, 2, 3, 4, 5

Events and multithreading

Sat, 15 Jul 2006 13:53:48 GMT

Rather interesting discussion on the microsoft.public.dotnet.languages.csharp group about events and multithreading.

Resume: thread-safe event is not an easy issue

Major features of .NET 2.0

Sun, 02 Jul 2006 09:55:32 GMT

Patrick published the list of major features of .NET 2.0

Source: http://www.codeproject.com/books/net2_cs2_newfeatures.asp

Extending the base class library collection classes of .NET 2.0

Sat, 18 Feb 2006 13:46:08 GMT

Peter Golde (formerly a Lead Designer for the C# language) incorporates the ideas from communities, relates to extending .NET 2.0 collections classes, into freely available library "Power Collections".

The list of collections includes: Dictionary, MultiDictionary, Set, Bag, OrderedDictionary, OrderedMultiDictionary, OrderedSet, OrderedBag. These classes were overwritten with extended functionality.

Specification about these collections is here: http://www.wintellect.com/powercollections/spec.aspx

In-process asynchronous services

Wed, 15 Feb 2006 14:11:43 GMT

Today world is changing to use async more and more. Gerald Gibson shows his representation of InProc async service.

Detailed description is here: http://www.codeproject.com/csharp/inprocessasynservicesincs.asp

Changes in ADO.NET for .net 2.0

Wed, 19 Oct 2005 13:38:00 GMT

As most of us working on the .NET 2.0 have seen a lot of pretty chagnes that were missed in first version. I'll try to review some of them related to ADO.NET.

Merging and XMLing of tables is really for tables ;) Now we can perform table merging and XMLing with DataTable, without wrapping them in DataSet
DataSet can be binary serialized, that gives us good productivity. And finally, i reckon, it states WebServices above Remoting (I don't want now discuss this point, but in .net 1.x WS was slightly behind Remoting due to XML serialization. Now it's not a bottleneck). Bye-bye Remoting (it's only my point of view)
Disconnected DataReader. Now we get totally disconnected DataReader - DataTableReader - for the most crucial parts of our data layer.

About all other changes and detailed description read the related topic of MSDN and John Papa new article.

Keep Your Code Running with the Reliability Features of the .NET Framework

Fri, 23 Sep 2005 20:55:54 GMT

This article shows how to make your code robust - to avoid OutOfMemoryException, StackOverflowException, and ThreadAbortExceptions by using Constrained Execution Regions.

An Extensive Examination of Data Structures in .NET

Tue, 23 Aug 2005 13:15:19 GMT

For FW 1.1 and FW 2.0

.NET multithreading articles

Wed, 10 Aug 2005 08:09:45 GMT

There I'd like to post a bunch of .NET multithreading articles:

1) Concurrency programming: http://blogs.msdn.com/larryosterman/archive/2005/2/11.aspx

"...processor has no way of accessing 64bit addresses atomically. What that means is that when a 32bit processor writes a 64bit value, it does it in two memory operations. So, when I wrote my original comment, I was thinking about the memory write case - relying on the fact that on 32bit processors, a natively aligned 32bit memory read is guaranteed to be atomic (and for 64bit processors, a 64bit aligned memory read is similarly guaranteed to be atomic). On currently supported 32bit processors, however a 64bit memory read is guaranteed to NOT be atomic..."

2) How to control your background tasks

3) Concurrency: What Every Dev Must Know About Multithreaded Apps

http://msdn.microsoft.com/msdnmag/issues/05/08/Concurrency/default.aspx

4) How to stop a Thread

If we want to interrupt thread, using Thread.Abort() is hazardous way doing this. The reason is that it raises an asynchronous exception we can't catch in proper place, even with using statement. For example, let's our thread's code is in the middle of the finally block, for the current moment, and performs clearing resources. If in exactly that moment ThreadAbortException is raised the remainder of the finally block won't run to completion.
Detailed description is here: http://www.interact-sw.co.uk/iangblog/2004/11/12/cancellation and extended samples is here http://www.dotnetconsult.co.uk/weblog/PermaLink.aspx/4f52c396-1b0d-4419-8871-6ca6992460ca

5) Fast Realization of .NET Read-Write Lock
http://blogs.msdn.com/vancem/archive/2006/03/28/563180.aspx

There are several ways to do effecient multithreaded syncronizations

Avoid locks on reads

Spin Lock

Raw Interlocked operations

Lazyinit

And Spin Lock is the best substitute for the slow Read-Write Lock.

6) Avoid and Detect Deadlocks
http://msdn.microsoft.com/msdnmag/issues/06/04/Deadlocks/default.aspx

7) Using concurrency for scalability
http://msdn.microsoft.com/msdnmag/issues/06/09/CLRInsideOut/

8) Concurrency and the impact on reusable libraries
http://www.bluebytesoftware.com/blog/PermaLink,guid,f8404ab3-e3e6-4933-a5bc-b69348deedba.aspx

9) Concurrency and Coordination Runtime
The CCR is a CLR library that provides a consistent and scalable way to program asynchronous operations and coordinate among multiple responses.
http://msdn.microsoft.com/msdnmag/issues/06/09/concurrentaffairs/default.aspx

Using AMD64 platform

Sat, 25 Jun 2005 16:57:03 GMT

В процессе использования AMD64 и Windows XP 64bit опытным путем было выявлено, что данная Windows, а собственно и процессор еще пока слишком раны для домашних приложений. Вот с чем пришлось столкнуться и какое ПО не работает:

Cisco VPN client (самое критичное, т.к. из дома работаю по вечерам)
кряк на аську
RealPlayer выводит сообщение, что не работает на 64bit системе
Diamon Tools для создания Virtual CD

Из плюсов:

Винда быстрей грузится, заметно на глаз
Есть 64bit драйвера на материнку на сайте производителе
FarCry(!), патч для AMD64 намного улучшает графику, все становится видно намного далеко. Вот ссылка на скриншоты игры сделанные на 32х и 64х битных платформах http://www.amd.com/us-en/Processors/DevelopWithAMD/0,,30_2252_869_875%5e10543,00.html?redir=IEGFC01