MimeParserBenchmark

This project benchmarks various .NET MIME parsers for comparison purposes.

Package Versions

Package	Version
MimeKit	3.0.0
LimiLabs' Mail.dll	3.0.21294.1630
Mime4Net	1.8.1
AE.Net.Mail	1.7.10
MailSystem.NET	2.0.1
OpenPOP.NET	2.0.6.1120

Runtime

Intel Core i7-9700 CPU 3.00GHz, 1 CPU, 8 logical and 8 physical cores
  [Host]     : .NET Framework 4.8 (4.8.4420.0), X64 RyuJIT
  DefaultJob : .NET Framework 4.8 (4.8.4420.0), X64 RyuJIT

Results

HeavyHeaderEmailBenchmark

In this benchmark, each library is used to parse an in-memory email message that is almost all headers 1,000 times.

Method	Mean	Error	StdDev
MimeKit	30.22 ms	0.207 ms	0.183 ms
MimeKitPersistent	30.08 ms	0.311 ms	0.276 ms
LimiLabs	629.92 ms	3.252 ms	2.883 ms
Mime4Net	517.56 ms	3.442 ms	3.051 ms
OpenPOP	353.23 ms	4.355 ms	4.074 ms
AENetMail	2,862.46 ms	17.677 ms	16.535 ms
MailSystemNET	1,911.98 ms	11.197 ms	10.474 ms

JwzMboxBenchmark

In this benchmark, each library is used to parse the jwz.mbox Unix mbox spool from disk 10 times.

Method	Mean	Error	StdDev
MimeKit	171.3 ms	0.87 ms	0.77 ms
MimeKitPersistent	160.1 ms	1.50 ms	1.33 ms
LimiLabs	1,148.3 ms	8.28 ms	7.75 ms

StarTrekEmailBenchmark

In this benchmark, each library is used to parse startrek.eml from disk 1,000 times.

Method	Mean	Error	StdDev
MimeKit	218.6 ms	1.95 ms	1.73 ms
MimeKitPersistent	205.5 ms	1.72 ms	1.61 ms
LimiLabs	2,318.0 ms	12.37 ms	10.96 ms
Mime4Net	10,726.6 ms	38.19 ms	35.73 ms
OpenPOP	NA	NA	NA
AENetMail	3,897.4 ms	74.18 ms	69.39 ms
MailSystemNET	8,928.0 ms	29.92 ms	26.53 ms

Notes:

• MailSystem.NET's parser only supports parsing from byte[] or MemoryStream, so in this test, MailSystem.NET is allowed to "cheat" by parsing an in-memory version of the message instead of being forced to parse from disk in each iteration.
• OpenPOP.NET fails to parse this message with the following exception:

System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.ArgumentException: Media Type must be in the format type "/" subtype
Parameter name: mediaType
   at OpenPop.Mime.Header.HeaderFieldParser.cleanMediaType(String mediaType)
   at OpenPop.Mime.Header.HeaderFieldParser.ParseContentType(String headerValue)
   at OpenPop.Mime.Header.MessageHeader.ParseHeader(String headerName, String headerValue)
   at OpenPop.Mime.Header.MessageHeader.ParseHeaders(NameValueCollection headers)
   at OpenPop.Mime.Header.HeaderExtractor.ExtractHeadersAndBody(Byte[] fullRawMessage, MessageHeader& headers, Byte[]& body, IParsingErrorHandler parsingErrorHandler)
   at OpenPop.Mime.MessagePart.ParseMultiPartBody(Byte[] rawBody)
   at OpenPop.Mime.MessagePart.ParseMultiPartBody(Byte[] rawBody)
   at OpenPop.Mime.Message.Load(Stream messageStream, IParsingErrorHandler parsingErrorHandler)
   at Benchmarks.StarTrekEmailBenchmarks.OpenPOP()
   at BenchmarkDotNet.Autogenerated.Runnable_14.WorkloadActionNoUnroll(Int64 invokeCount)
   at BenchmarkDotNet.Engines.Engine.RunIteration(IterationData data)
   at BenchmarkDotNet.Engines.EngineFactory.Jit(Engine engine, Int32 jitIndex, Int32 invokeCount, Int32 unrollFactor)
   at BenchmarkDotNet.Engines.EngineFactory.CreateReadyToRun(EngineParameters engineParameters)
   at BenchmarkDotNet.Autogenerated.Runnable_14.Run(IHost host, String benchmarkName)
   --- End of inner exception stack trace ---
   at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)
   at System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments)
   at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
   at BenchmarkDotNet.Autogenerated.UniqueProgramName.AfterAssemblyLoadingAttached(String[] args)

Xamarin3EmailBenchmark

In this benchmark, each library is used to parse xamarin3.eml from disk 1,000 times.

Method	Mean	Error	StdDev
MimeKit	1.629 s	0.0168 s	0.0157 s
MimeKitPersistent	1.344 s	0.0086 s	0.0080 s
LimiLabs	12.503 s	0.0421 s	0.0394 s
Mime4Net	85.075 s	0.4774 s	0.3987 s
OpenPOP	80.162 s	0.6835 s	0.6059 s
AENetMail	30.925 s	0.2161 s	0.1915 s
MailSystemNET	48.179 s	0.6107 s	0.5713 s

Notes:

• MailSystem.NET's parser only supports parsing from byte[] or MemoryStream, so in this test, MailSystem.NET is allowed to "cheat" by parsing an in-memory version of the message instead of being forced to parse from disk in each iteration.

Conclusions

Yea. No contest. MimeKit mops the floor with all of the other parsers out there.

How does your MIME parser compare?