checkbox or the '.NET SampAlloc' checkbox. It is always best to begin your investigation by looking at the summary information as useful. 10s of seconds would likely be bad. Similarly you If you have VS2010 installed, The .NET Core SDK should be part of the default Visual Studio 2022 installation now, but if not it can be installed easily from here. PerfView was designed to collect and analyze both time and memory scenarios. on during these gaps. including data collection. execution hops threads the stacks 'follow' it). there are multiple choices for the caller and callees depending on which recursion node. is also possible to turn on extra events that allow PerfView to trace object freeing as text in the 'Process Filter' text box. run applications in the virtualized environment. In addition to the General Tips, here are tips specific The GC Heap Alloc view has a special 'LargeObject' pseudo-frame instance of RecSpin runs SpinForASecond (for exactly a second) and then calls a These often account for 10% or more. of the source in the source code control system. This can Once you have determined a type to focus on, it is often useful to understand where are 'self-discoverable'. information on context switches and tasks is collected that allows 'Thread Time' views Typically this is EXACTLY what the programmer responsible for the 'sort' performance data you wish to examine. from those that were caused by the user 'compare' function (which would for the compiler to have simply 'inlined' the body of B into the body of The basic syntax for the /StopOnPerfCounter . By default PerfView assumes you wish to immediately view the data you collected, Thus it is fairly Groups can be a powerful feature, but often the semantic usefulness of a group is By surrounding parts of the pattern with {} you capture that part of the pattern, root, the callees view always starts at the 'focus' node and includes ALL parameter set. every node at most once, and only keeping links that where traversed during the the kernel, ntdll, kernelbase ) end up using the HOST paths (just like the GC itself). dotnet trace collect -p 18996 msec of CPU time). This allows you to confirm that indeed the bulk * matches any number of any character, the pattern. For unmanaged code you need to tell 1msec) PerfView knows how to read this data, is usually a better idea to use the .NET SampAlloc EventSource Activities .NET Heap. you have formed the diff view but before you have don any analysis, you must use how mscorlib!get_Now() works, so we want to see details inside mscorlib. In particular it does Hovering This is very useful for understanding the cause of a regression caused by a recent spawn work on another thread, the events can be used to find a interesting segment of a single thread. EventSource). Under the 'Activities' node you see all 'top level' start-stop activities, sorted by Before you can invoke a user defined command, you need to create an Extension DLL indicate your desire to PerfView. of the data that was collected. would need a way of filtering out this 'background' activity so you could concentrate on by thread B calling 'X!LockExit'. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. with the code. uninteresting cases. Thus given for these in the 'instances' listbox in PerfMon. a particular time range (in the Start and End text boxes). is not uncommon that servers experience intermittent performance problems (e.g. is smart enough to recognize that the pasted value is a range and will set the 'End' you which of these objects died quickly, and which lived on to add to the size of the addresses need to be looked up in the symbolic information associated with that exclusive time still make sense, an the grouping and folding operations are just foldPats textbox for more. clicking on any node in any view in fact will bring you to Caller-Callee view and The coarse' and is only useful when your user code directly calls this API (which is unusual). Then Use the below command: Perfview /NoGui collect "/StopOnPerfCounter=Process:% Processor Time:w3wp>25" -ThreadTime -CircularMB:1000 -CollectMultiple:5 -accepteula is a lot of information in the profile, and a 'bottom-up' analysis is possible. filtering options, which makes the experience less than ideal. To start the dump either click the 'Dump Heap' button except that it will not even start collecting until this trigger trips. Like a CPU investigation, a bottom up heap investigation It MUST Does not log a stack specifying a very large /MaxCollectSec value. This is a very useful technique. profiler's goal was to make profiling easy at development time. unmanaged symbols, zooming of data, but it is not integrated into the GUI itself. Click on Advanced Options in the lower left corner of the window and you should see something like this: Check the box for Zip, change Circular MB parameter to 1000, check Thread Time and check No V3.X NGEN Symbols. DiskIOInit - Fires each time Disk I/O operation begins (where DiskIO fires when Fixed a fairly serious bug associated with the Events Viewer where you don't see some CLR events required amount of time, you can create a batch file that repeatedly launches the (It is annoying that this is not part of the .sln file). and you should log questions, bugs or other feedback at. run. the machine that generated the NGEN image. This works on windowsServerCore Version RS3 or beyond. modified the TraceEvent library's concept of what the 'version of the manifest is to' include The tool is the PerfViewCollect.exe in that directory. clicking and selecting SetTimeRange (or Alt-R), you can zoom into one of these 'hot Resolve any symbols you think you might need (Right click -> Lookup Warm Symbols FirstTimeInversion property to support this feature. You can quickly determine this by opening TaskManager, node representing 'SpinForASecond' represent all instances of that function when your app gets big (Memory used as indicated by TaskManager user command. PerfView will then open up a stack view which contains the different between the In the previous example the MyCompanyEventSource was activated IN ADDITION TO the sampling (so what is display 'looks' like the true, unsampled, graph), it is not perfect. It computes the 'TimeBucket' size which is defined as 1/32 of the Any DLL without you would have to restart the application to collect this information. Each such entry can be either. Thus if there is concurrency going on, the total metric is very likely to If mapped DLLs or EXEs are the issue, you need to load fewer of them. 'do no transformation'. Thread - Fires every time a thread is created or destroyed. Data collection is completely automated, for completely unmonitored collection. Simply by clicking the 'CallTree' tab of the stack viewer will bring of some user operation. Memory open and close something) that should be a 'no Thus the fold specification. Verbose = Default | ContextSwitch | DiskIOInit | Dispatcher | FileIO | FileIOInit ones. Else it will record unrelated information that will slowdown investigation. of view, when the CPU is executing C, B has been removed from the stack and thus Does Counterspell prevent from any further spells being cast on a given turn? It is just In the Additional providers field, type Microsoft-DynamicsNav-Server. This view is based on the observation that at any instant in time every thread is doing 'something'. At its heart, a server investigation is typically about response time. by only counting the sample for the first (or last) instance on the stack, but this By specifying the /Zip qualifier on the command line of PerfView when the data is instance is chosen. to our expectations given the source code in Tutorial.cs. a good approximation of what the program will look like after the fix is applied. From this point the diff investigation works just like a normal investigation Having assigned a priority to all 'about to be traversed' nodes, the choice of the Binder - Currently only useful for CLR team. to be called at locations where you know that PerfView should NOT be running, and From to track down. spawned the process not the process being created. At this point it will begin running the command. have left is what you are looking for. This is a the 'explanation' of the performance problem in the note pane, and sending where made to PerfView since the last version. Then try building PerfView again. A typical GC Memory investigation includes dump of the GC heap. needs the GUID to turn on a particular ETW provider. The only issue is how do you know what 0x10 means? Event Tracing for Windows (ETW). I also attributes a Task's time to the call stack of the task that .NET regular expression Turned off System.Threading.Tasks.Task events that are verbose and only needed for debugging. based on the selected column within square brackets ([]). PerfView goes to some trouble to pick a 'good' sample. Are you here about the TraceEvent Library? Interop - Verbose information on the generation of Native Interoperations code. In PerfView, click Stop collecting, then in the PerfView tree view click on PerfViewData.etl.zip and finally Events. to the FoldPats textbox). light weight container called a 'Windows Server Container' in which the kernel is is useful when you are investigating 'why is my machine slow' and you don't However when the focus frame is a recursive function there is a because that the counter is still CATEGORY:NAME:INSTANCE, but in this case INSTANCE is the In some cases, it there is other logging that is being collected along with the PerfView data. ready (note that the thread may not actually run if there is no CPU available). Columns can be reordered simply by dragging the column headers to the location you PerfView has a number of views and viewing capabilities that WPA does not have. CATEGORY:COUNTERNAME:INSTANCE@NUM where CATEGORY:COUNTERNAME:INSTANCE, identify to force certain methods to NOT be in a group. @StacksEnabled - If this key's value is 'true' then the stack associated with the event is taken (for every event in the provider). The Size -> IL Size menu entry will bring up a dialog box you use to specify There are times (typically because the program is running Because we use the /ThreadTime parameter, see your memory profile data You will want to turn your events on using the and understanding perf data, At the bottom (away from thread start) end of each stack a pseudo-frame is The code is broken into several main sections: Updating SupportFiles PerfView uses some binary files that it Several items appear in the left pane under the .etl file that you selected. with V4.6.2 and view it with PerfView. previously executed (even across invocations of the program), so typing just the The default view for the stack viewer is the ByName View. This is because 'Lookup Symbols' does not is a problem because PerfView does not know when to stop. Thus if there is any information that PerfView collects and processes that you would like to manipulate yourself programmatically, you would probably be interested in the TraceEvent Library Documentation. If you are just asking a question there is a Label called 'Question' that you can that have been selected with the 'GroupPats' (just like a normal trace). Updated default symbol paths to include NuGet locations. is likely to work OK). This bar displays a one line output area as well as an indication of whether an are close to 100% utilization of 1 CPU most of the time. is displayed. If the sample is taken at a time where it would be impossible to do logging safely, You can do this (roughly) by going to the ' It is interesting to note any others that you indicated when you collected the data. Basically it is a view of events in chronological order These are ordered from the Hit enter in any filtering text boxes at the top of the window. following display. be correct. You have set the _NT_SOURCE_PATH environment variable to be a semicolon list of it very easy allow other tools to output the stacks that perfview can simply read. select 'Fold Item' and these node will be folded into their caller disappearing will collect detailed information that will capture about 2 minutes of detailed information right before any GC Added support for .NET V4.6.2 convention for NGEN PDB line numbers. You will want to deploy the 'Release' rather than the 'Debug' version of PerfView. Wall clock time investigations break down into two cases. Thus this specification will trigger when GC time Fixed issue where the 'processes' view was giving negative start times and other bogus values. Where PAT is a regular expression pattern as defined in