Consider limiting task-input logging character max

[rainersigwald]

An internal partner reported (see AB#1019268) out-of-memory errors in VS when using their large solution. @merlynoppenheim debugged and discovered that LogTaskInputs was enabled (by Project System Tools turning on binary logging for design-time builds), and a huge amount of memory was attributable to ItemGroupLoggingHelper.GetParameterText building up strings to log.

In the project in question, there was a single task that tried to log 9966 items, each with ~60 metadata values, some of which were long (I caught one at 172,800 characters and one at 51,860).

We should consider having an on-by-default cap on how much gets logged. It's not useless to log all of this input: you can imagine pulling it out of the log and doing something useful with it. But there's surely a point of diminishing returns between logging one input (yes! Definitely!) and logging a megabyte of text (is this actually useful?).

We spitballed a limit like "the first 10k characters of the item inputs as text".

[rainersigwald]

Related to #2200, but a different approach: instead of avoiding creating LOH strings, just discard (part of) them.

[rainersigwald]

This might be a duplicate of #2168, though.

[omnigoat]

Hi there. I'm pretty sure we're hitting this whilst running a custom-build step of ours. We have an intermittent failure of a custom-build step, with many inputs. The length of the Inputs field is over 190k characters long. See the bug I filed here: https://developercommunity.visualstudio.com/content/problem/804881/visual-studio-2019-cant-run-custombuildstep-with-l.html?childToView=825578#comment-825578

After further debugging, two different callstacks surface (reproduced below), both in regards to logging. Turning MSBuild project build output verbosity to Quiet works around this issue. This is not a suitable workaround.

Is there a way we can rewrite this as a task or something to avoid this? It's a severe blocker. Thanks!

System.OutOfMemoryException: Exception of type 'System.OutOfMemoryException' was thrown.
   at System.Text.StringBuilder.ToString()
   at Microsoft.Build.Shared.ReuseableStringBuilder.ToString()
   at Microsoft.Build.BackEnd.ItemGroupLoggingHelper.GetParameterText(String prefix, String parameterName, IList parameterValue)
   at Microsoft.Build.BackEnd.ItemGroupIntrinsicTask.ExecuteRemove(ProjectItemGroupTaskItemInstance child, ItemBucket bucket)
   at Microsoft.Build.BackEnd.ItemGroupIntrinsicTask.ExecuteTask(Lookup lookup)

System.OutOfMemoryException: Exception of type 'System.OutOfMemoryException' was thrown.
   at System.String.Split(String[] separator, Int32 count, StringSplitOptions options)
   at Microsoft.Build.BackEnd.Logging.BaseConsoleLogger.IndentString(String s, Int32 indent)
   at Microsoft.Build.BackEnd.Logging.BaseConsoleLogger.WriteLinePretty(Int32 indentLevel, String formattedString)
   at Microsoft.Build.BackEnd.Logging.SerialConsoleLogger.MessageHandler(Object sender, BuildMessageEventArgs e)
   at Microsoft.VisualStudio.ProjectSystem.VS.Implementation.Build.VsOutputWindowFormatter.AnyEventRaisedHandler(Object sender, BuildEventArgs args)
   at Microsoft.Build.Utilities.MuxLogger.SubmissionRecord.RaiseAnyEvent(Object sender, BuildEventArgs buildEvent)
   at Microsoft.Build.BackEnd.Logging.EventSourceSink.RaiseAnyEvent(Object sender, BuildEventArgs buildEvent)

[KirillOsenkov]

Also improved by #6155