Archive for category Diagnostics
Structured logging (also sometimes called semantic logging) is a useful addition to the software development toolkit.
The latest release (2.2.0, and some 2.1.728) of Essential.Diagnostics adds structured tracing capabilities to the .NET Framework System.Diagnostics. It integrates seamlessly with existing tracing, including from the .NET Framework, and includes both producer-side extensions (to include in your application) and trace listener changes (to integrate with structured tracing systems).
The key new and updated packages are:
While the packages can be used independently, using both a producer and consumer in combination multiplies the benefits.
Following hot on the heels of v2 of Essential.Diagnostics, work on the beta version of the Essential.Diagnostics.SeqTraceListener has been completed, and it has been published to NuGet.
PM> Install-Package Essential.Diagnostics.SeqTraceListener
This provides a trace listener implementation that forwards messages to a Seq logging server. For performance it forwards messages in batches (with the first message being sent immediately, so you know the system is up and running), with automatic back off and retry when there are interruptions to the network communication.
This component can be used with the new Microsoft.Extensions.Logging for .NET 4.5.1 and above, or with Sytem.Diagnostics.TraceSource for .NET 2.0 through 4.5.
I have made significant changes in the organisation of the Essential.Diagnostics project; although none of the actual implementations have changed, the project has been split into separate packages for each trace listener, available via NuGet.
The project also has a new logo:
This was originally going to be some guideline instructions for a CodePlex project, Essential.Diagnostics that I work on, but it ended up being more an opinion piece so I thought it would fit better on a blog.
There are several trace listeners (loggers) in the .NET Framework that can produce XML output. Outputting to XML results in more complex (verbose) files than, say, a simple text file output, but usually has the benefit of being better processed by tools, correlated across tiers, etc.
There are three main XML listeners, plus one extension in Essential.Diagnostics:
- RollingXmlTraceListener (in Essential.Diagnostics)
- EventSchemaTraceListener (in System.Core)
- EventProviderTraceListener (in System.Core)
Examples of how to configure and use each one (used to produce the output below) is provided in the Essential.Diagnostics project.
Read the rest of this entry »
I added a comparison of the major logging/tracing frameworks for .NET to the CodePlex site for Essential.Diagnostics, to demonstrate how System.Diagnostics stacks up against log4net, NLog and the Enterprise Library.
I also added a performance comparison (the source code is in the CodePlex project if you want to verify the results).
Look at the results for yourself, but I think System.Diagnostics does okay — and the extensions in Essential.Diagnostics (plus others such as Ukadc.Diagnostics and UdpPocketTrace) fill out the gaps compared to log4net and NLog. Similarly on the performance side, all have very little overhead (NLog is a winner on overhead, but does relatively worse on actually writing the messages to a log file).
What about the Enterprise Library Logging Application Block? Well, I just don’t think it does well compared to the others. Sure it was a lot better than .NET 1.0 System.Diagnostics, but a lot of that was added in .NET 2.0 System.Diagnostics (such as multiple sources). In some cases it is worse than what is currently available in the standard framework — e.g. no delayed formatting. This shows up in the performance figures which indicate several magnitudes greater overhead than any of the other frameworks!
I’m obviously biased, but I really think that the best solution is to stick with the standard, out-of-the-box, System.Diagnostics, extended where necessary to fill any gaps (Essential.Diagnostics, etc, for additional listeners, filters & formatting).
P.S. Also check out my guidance on Logging Levels.
According to MSDN “in Microsoft SharePoint Foundation 2010 the preferred method of writing to the Trace Logs is to use the SPDiagnosticsServiceBase class” (http://msdn.microsoft.com/en-us/library/ff512746.aspx).
MSDN also provides some guidance on the trace and event log severity levels to use (http://msdn.microsoft.com/en-us/library/ff604025.aspx), however the WriteEvent() and WriteTrace() methods use slightly different enums; the diagnostics logging configuration in Central Administration is slightly different again, and then you have a third set of values accessed by the PowerShell command Get-SPLogEvent.
The table below shows the mapping of levels from these different sources.
Despite the complicated mapping, in general I think things go in the right direction with events writing to the event log and trace log at the same time, and having a high trace level. The distinction between event logging and trace information is also good, with independently set thresholds.
|None = 0||None = 0||0 (None)||Unassigned = 0|
|ErrorServiceUnavailable = 10||Error||1||Critical = 1 (or ErrorCritical)|
|ErrorSecurityBreach = 20|
|ErrorCritical = 30|
|Error = 40|
|Exception = 4|
|Assert = 6|
|Warning = 50||Warning||8||Warning = 8|
|FailureAudit = 60|
|Unexpected = 10||Unexpected = 10||Unexpected = 10|
|Monitorable = 15||Monitorable = 15||Monitorable = 15|
|SuccessAudit = 70||Information||18||Information = 18|
|Information = 80|
|Success = 90|
|Verbose = 100|
|High = 20||High = 20||High = 20|
|Medium = 50||Medium = 50||Medium = 50|
|Verbose = 100||Verbose = 100||Verbose = 100|
|VerboseEx = 200||VerboseEx = 200||VerboseEx = 200|
Essential.Diagnostics is a library of additional trace listeners and other bits for the .NET Framework System.Diagnostics trace logging.
It doesn’t change the way you write log statements (you still use TraceSource), but fits into the built-in extension points to add functionality (mostly additional trace listeners and filters).
From the project description:
“Essential.Diagnostics contains additional trace listeners, filters and utility classes for the .NET Framework System.Diagnostics trace logging. Included are colored console (that allows custom formats), SQL database (including a tool to create tables) and in-memory trace listeners, simple property and expression filters, activity and logical operation scopes, and configuration file monitoring.”
The intention is to round-out System.Diagnostics with additional capabilities so that it can be compared to alternative 3rd party logging systems (NLog, log4net, Common.Logging, and even Enterprise Library).
Note that the library is intentionally much lighter than Enterprise Library; rather than an overhaul of the logging mechanism itself the library is mainly meant to provide additional trace listeners.
I put the source code up a few days ago, but only recently finished the packaging scripts for the downloads.
With the recent release of
NuPack NuGet, I have also spent an additional bit of time and set it up as a NuGet package.