Latest Microsoft Blogs

For all of you who have been asking me if there is a 64bit version of Debug Diag (used to debug 64 bit processes), I am happy to say that yes, Debug Diag 1.1 64bit is now released. You can download it here: http://www.microsoft.com/DOWNLOADS/details.aspx?FamilyID=28bd5941-c458-46f1-b24d-f60151d875a3&displaylang=en#filelist And an updated whitepaper talking about how to use it is available here: http://www.microsoft.com/downloads/details.aspx?familyid=4A2FBD0D-0635-440C-A08B-ED81BDBB5960&displaylang=en Neither this version (nor the 32bit one) officially support debugging/analyzing on Vista/2008/Win7 because of some known compatibility issues (being looked at for future versions), however for a lot of tasks it works quite well on those...

I had an interesting case today where an asp.net app was stuck in a true deadlock.  In other words two threads were both waiting for resources that the other thread owned. The scenario in these cases usually goes something like this: FunctionA (locks on ResourceA) and calls FunctionB where it needs ResourceB FunctionB (locks on ResourceB) and calls FunctionA where it needs ResourceA And is typically pretty easy to spot, understand and fix… However, in this particular case things were a bit different. We had gotten memory dumps of the process and after loading them up in windbg, loding sos.dll, and running ~* e !clrstack to see what the threads were working on, we found that a lot of the threads were sitting in System.Threading.Monitor.Enter...

I got an email today on an issue that I think is pretty common when you try to memory leak analysis on a dump with debug diag . They had set up a leak rule in debug diag to monitor for leaks and then ran the memory analysis on it to see what was leaking and the results looked something like this:   Warning mscorwks.dll is responsible for 372.46 MBytes worth of outstanding allocations. The following are the top 2 memory consuming functions: mscorwks!EEVirtualAlloc+119 : 312.00 MBytes worth of outstanding allocations. mscorwks!EEHeapAlloc+142 : 60.46 MBytes worth of outstanding allocations. If this is unexpected, please contact the vendor of this module, Microsoft Corporation , for further assistance with this issue. So what does this mean...

I was out looking for some sample scripts for tinyget and ran across this ANTS Memory Profiler review where Scott Seely has tested it out on some of my debugging labs . I haven’t had the time and/or opportunity to test it out myself but since many people have asked me if I had used it or what I thought of it I thought I’d just point you to someone who has instead:) Have fun, Tess Read More...

The other day I came across an issue where an ASP.NET site stopped responding and didn’t start serving requests again until the W3WP.exe process was restarted. We grabbed some memory dumps with debug diag before restarting the process to see what was going on. Debugging the dumps: I opened the dump in windbg, and loaded up sos (.loadby sos mscorwks). As with all hang dumps I usually check what the threads are doing (~* kb) and I found that one thread (10) was initiating a garbage collection. 0:010> kb ChildEBP RetAddr  Args to Child              01cceeb4 7c827d0b 77e61d1e 00000280 00000000 ntdll!KiFastSystemCallRet 01cceeb8 77e61d1e 00000280 00000000 01cceefc ntdll!NtWaitForSingleObject...

Some time ago Jim Cheshire wrote a book on VWD 2008 and recently book publisher kindly allowed us to provide four chapters as free downloadable PDF files. The following chapters are available: Creating Web sites Creating and Managing CSS Styles Applying CSS to Web Forms Debugging ASP.NET Applications You can find link to download at VWD section on ASP.NET Web site (look for Visual Web Developer Books section at the right side) or download ZIP file directly from here . We hope you will find them useful. - Mikhail Arkhipov Read More...

With Visual Studio 2010 and .NET 4.0 getting ready to be shipped sometime in the next year, I wanted to see what were peoples ideas for how to debug applications that were written with them.  Are you happy in production with what you are currently doing?  Do you use SOS.dll to troubleshoot problems? SOS The main place I am really interested in is production debugging.  Is SOS a sufficient tool to get the data that you need?  If you had another version of SOS for .NET 4.0, would you be happy with the features it has or would you want something more? Debugger I understand that using a typical debugger can be very difficult for people.  If you don’t know what you are looking at, it can be very difficult to understand what...

Summer is almost over and a new season of heavy work is beginning.  I wanted to take this opportunity to start on a new page and make sure that I’m spending my cycles doing the right things.  I’ve been blogging for almost 3 years now and throughout the blogs life I’ve been blogging pretty much the same way, trying to show examples of where me and fellow developers have gotten into situations that have caused crashes, memory leaks, exceptions, hangs etc., so that we can all learn from the situations and avoid them. Throughout the 3 years I have gotten a lot of comments saying that posts have helped developers, but I have also gotten more private comments saying that what I am talking about lies so far out of their realms that they don...

I came back from a long vacation today and I’ve finally caught up with enough emails to do something useful with my day. As I scanned through my blog email bucket I noticed that I had a lot of emails relating to my last post on dumping .net exceptions in windbg , and most of them asked why they see OutOfMemoryExceptions on the heap, and how to troubleshoot this. I think I have mentioned this before, but it seems like it is worth mentioning again as it is probably buried deep in some post from way back when… When you dump out all the exceptions on your .net GC heap (using !dumpheap -type Exception for example) these 3 types of exceptions will always show up, independently of what type of .net process you are debugging. 79330c30       ...

This is a quick post to cover few items related to Script Debugging and the way it is impacted by Silverlight, Internet Explorer 8 and Visual Studio 2010… With IE 8 there is no longer option to disable script debugging… When VS 2010 will launch IE 8 then script debugging will be enabled by default… This will help people debug scripts flawlessly without having to go and change script debugging features within IE 8… While this is a good feature for most users it might at times create problem when you do not really want script debugging to be enabled for performance reasons (i.e. if you do not want to debug scripts and have lot of scripts in your pages)… On separate note Silverlight is a special debugging option for Web Projects…  You can...