Missing/Broken Msiexec Circumventing CPU Stall Checks

While attempting to use BCU to uninstall a "broken" Zoom msiexec install (the uninstall media was missing), I noted that msiexec sometimes will be using 10%+ CPU when it is doing nothing but sitting at this screen:

Currently the UninstallThread() method in BulkUninstallEntry.cs is waiting for 30 consecutive true returns from TestUninstallerForStalls() saying that the process is using less than 1% CPU and 10KB of IO, however in my test case, the process will infinitely run, as msiexec is running at 10%+ CPU but with 0 I/O. I have two solutions to this that I have tested successfully locally:

The easy fix

Simply make the CPU and IO checks an or instead of and:

Current: https://github.com/Klocman/Bulk-Crap-Uninstaller/blob/f18ce757f3c4edd219c123211f4209ffa0f5a726/source/UninstallTools/Uninstaller/BulkUninstallEntry.cs#L262 Proposed:

if (c0 <= 1 || c1 <= 10240)

While I do not have solid data to back this up, my assumption would be that if an uninstaller does not perform any IO work or any CPU work in 30 seconds then it is likely stalled. I am open to suggestions/corrections here as this is simply an assumption.

The possibly more robust fix

Add a new property and constructor parameter to RunUninstallerOptions to allow for an optional "timeout":

Current: https://github.com/Klocman/Bulk-Crap-Uninstaller/blob/f18ce757f3c4edd219c123211f4209ffa0f5a726/source/UninstallTools/Uninstaller/BulkUninstallEntry.cs#L615-L635

Proposed:

internal sealed class RunUninstallerOptions 
 { 
     public RunUninstallerOptions(
bool autoKillStuckQuiet, bool retryFailedQuiet, bool preferQuiet, bool simulate, BulkUninstallTask owner,
/****New timeout property****/int timeout = -1) 
     { 
         AutoKillStuckQuiet = autoKillStuckQuiet; 
         RetryFailedQuiet = retryFailedQuiet; 
         PreferQuiet = preferQuiet; 
         Simulate = simulate; 
         Owner = owner;
         // ***New timeout property***
         Timeout = timeout;
     } 

     public bool AutoKillStuckQuiet { get; } 

     public bool PreferQuiet { get; } 

     public bool RetryFailedQuiet { get; } 

     public bool Simulate { get; } 

     public BulkUninstallTask Owner { get; } 

    // ***New timeout property***
    public int Timeout { get; }

 }

Use this timeout functionality where required to kill the uninstall process even if it is not being marked as "stalled". For instance:

Current: https://github.com/Klocman/Bulk-Crap-Uninstaller/blob/f18ce757f3c4edd219c123211f4209ffa0f5a726/source/UninstallTools/Uninstaller/BulkUninstallEntry.cs#L316-L319

https://github.com/Klocman/Bulk-Crap-Uninstaller/blob/f18ce757f3c4edd219c123211f4209ffa0f5a726/source/UninstallTools/Uninstaller/BulkUninstallEntry.cs#L375-L379

Proposed:

var idleCounter = 0;
Stopwatch watch = new Stopwatch();
if(options.Timeout > 0) { watch.Start(); }
while (true)

 // Kill the uninstaller (and children) if they were idle/stalled for too long 
 if (idleCounter > 30 || watch.ElapsedMilliseconds >= options.Timeout) 
 { 
     watch.Stop();
     KillProcesses(watchedProcesses); 
     throw new IOException(Localisation.UninstallError_UninstallerTimedOut);
// ... after the while loop
watch.Stop();

This would allow for all functionality to remain the same unless something explicitly implements the timeout.

I would be using this in my current fork to implement junk cleanup in BCU-console. If you'd like a PR for this, I'll be happy to put one together.

Klocman / Bulk-Crap-Uninstaller

Missing/Broken Msiexec Circumventing CPU Stall Checks #579

The easy fix

The possibly more robust fix