Using PowerEvents to capture Permanent WMI Events for SQL Server Blocking

I've been enthusiastically educating myself on PowerShell and how it can be used to monitor SQL Server and in the process discovered Trevor Sullivan's fantastic PowerEvents modules (thanks to a colleague - yo Chris!) and examples.  Specifically, Monitoring DB Mirroring and Monitor and Respond to Windows PowerEvents and Monitoring SQL Server and Using PowerEvents to Monitor Change in Database Options and DBA Solutions Using PowerShell.

These are all excelent examples and have helped tremendously to get me going in the right direction. But... (and you knew there was going to be a but)... the examples I've found have fallen short of what I'd like to be able to do... like my topic header states: <o:p></o:p>

Does PowerEvents (or, for that matter, any other PowerShell permanent eventing
subsystem) populate and pass along the automatic variables $Event, $SourceArgs,
etc so that one can consume and manipulate the triggering event's properties? <o:p></o:p>

My initial thought that this should be quite straightforward given Trevor's documentation andPowerEvents: WMI Event Consumers via using the CommandLineEventConsumer and passing event details via the special WMI %targetinstance% variable (would prefer not to have to write VBScript as that seems like a step backwards).

Problem (goal)<o:p></o:p>

Production SQL Server environments tend to encounter issues with intermittent and extended blocking which I'd like to persist to tables in an Admin database so that these can be analyzed later at a more convenient time. The link above by Junior Laerte was excellent in that it showed how to use sp_whoisactive to do this... and I've been successful in getting that to work (with some minor changes). In that link Junior suggests (and I would prefer) to accomplish this via more permanent eventing (ie, using the PowerEvents filter/consumer/binding model) versus the not-so-permanent method as he demonstrated here (Using PowerShell and WMI Events Queries) and here (Using PowerShell and SQL Server Events - Blocked Process Report).

However, before attempting to do the CommandLineConsumer to fire off PowerShell and capture sp_whoisactive (see last link above), I wanted to ensure that I can get to the point where a SQL Server blocking event fired off a permanent event that at least captures the details of the event.. then, modifying it so that it captures the actual blocking information.  So, this interim step - simple test to capture blocking event details - is what is described in what follows.

Here's what I've done so far and where it's failing:

• Created a simple PowerShell script to be executed by the event consumer named test.ps1 located at C:\scripts folder

"Made it to test.ps1 at $(get-date)"
$args | gm

• Successfully tested this from both PowerShell and DOS command prompt. NOTE: The %CD% will be replaced by %TargetInstance% WMI token once this works.
  

C:\windows\System32\WindowsPowerShell\v1.0\powershell.exe -command "C:\Scripts\Test.ps1 `"%CD%`" >>C:\Scripts\Test.out"

Made it to test.ps1 () at 04/05/2013 15:08:20
Z:\


   TypeName: System.String

Name             MemberType            Definition                                                                                                                                  
----             ----------            ----------                                                                                                                                  
Clone            Method                System.Object Clone()                                                                                                                       
CompareTo        Method                int CompareTo(System.Object value), int CompareTo(string strB)                                                                              
Contains         Method                bool Contains(string value)                                                                                                                 
CopyTo           Method                System.Void CopyTo(int sourceIndex, char[] destination, int destinationIndex, int count)                                                    
EndsWith         Method                bool EndsWith(string value), bool EndsWith(string value, System.StringComparison comparisonType), bool EndsWith(string value, bool ignore...
Equals           Method                bool Equals(System.Object obj), bool Equals(string value), bool Equals(string value, System.StringComparison comparisonType)                
GetEnumerator    Method                System.CharEnumerator GetEnumerator()                                                                                                       
GetHashCode      Method                int GetHashCode()                                                                                                                           
GetType          Method                type GetType()                                                                                                                              
GetTypeCode      Method                System.TypeCode GetTypeCode()                                                                                                               
IndexOf          Method                int IndexOf(char value), int IndexOf(char value, int startIndex), int IndexOf(char value, int startIndex, int count), int IndexOf(string ...
IndexOfAny       Method                int IndexOfAny(char[] anyOf), int IndexOfAny(char[] anyOf, int startIndex), int IndexOfAny(char[] anyOf, int startIndex, int count)         
Insert           Method                string Insert(int startIndex, string value)                                                                                                 
IsNormalized     Method                bool IsNormalized(), bool IsNormalized(System.Text.NormalizationForm normalizationForm)                                                     
LastIndexOf      Method                int LastIndexOf(char value), int LastIndexOf(char value, int startIndex), int LastIndexOf(char value, int startIndex, int count), int Las...
LastIndexOfAny   Method                int LastIndexOfAny(char[] anyOf), int LastIndexOfAny(char[] anyOf, int startIndex), int LastIndexOfAny(char[] anyOf, int startIndex, int ...
Normalize        Method                string Normalize(), string Normalize(System.Text.NormalizationForm normalizationForm)                                                       
PadLeft          Method                string PadLeft(int totalWidth), string PadLeft(int totalWidth, char paddingChar)                                                            
PadRight         Method                string PadRight(int totalWidth), string PadRight(int totalWidth, char paddingChar)                                                          
Remove           Method                string Remove(int startIndex, int count), string Remove(int startIndex)                                                                     
Replace          Method                string Replace(char oldChar, char newChar), string Replace(string oldValue, string newValue)                                                
Split            Method                string[] Split(Params char[] separator), string[] Split(char[] separator, int count), string[] Split(char[] separator, System.StringSplit...
StartsWith       Method                bool StartsWith(string value), bool StartsWith(string value, System.StringComparison comparisonType), bool StartsWith(string value, bool ...
Substring        Method                string Substring(int startIndex), string Substring(int startIndex, int length)                                                              
ToCharArray      Method                char[] ToCharArray(), char[] ToCharArray(int startIndex, int length)                                                                        
ToLower          Method                string ToLower(), string ToLower(System.Globalization.CultureInfo culture)                                                                  
ToLowerInvariant Method                string ToLowerInvariant()                                                                                                                   
ToString         Method                string ToString(), string ToString(System.IFormatProvider provider)                                                                         
ToUpper          Method                string ToUpper(), string ToUpper(System.Globalization.CultureInfo culture)                                                                  
ToUpperInvariant Method                string ToUpperInvariant()                                                                                                                   
Trim             Method                string Trim(Params char[] trimChars), string Trim()                                                                                         
TrimEnd          Method                string TrimEnd(Params char[] trimChars)                                                                                                     
TrimStart        Method                string TrimStart(Params char[] trimChars)                                                                                                   
Chars            ParameterizedProperty char Chars(int index) {get;}                                                                                                                
Length           Property              System.Int32 Length {get;}                        

• Created WMI event filter

ipmo powerevents
$DurationMilliSecs = 20000         #Duration of blocking in milliseconds; the WMI events gets kicked off at this interval
$WQLEventQuery = "select * from  BLOCKED_PROCESS_REPORT where duration > $DurationMilliSecs"
#Set the filter based on the blocked processes query
$Filter = New-WmiEventFilter -Name "SQLSERVER: Blocked Processes Duration" -Query $WQLEventQuery

• Created WMI event consumer and bound the filter to it

$Consumer = New-WmiEventConsumer -Name 'SQLServerblocking' -ConsumerType CommandLine `
-ExecutablePath C:\windows\System32\WindowsPowerShell\v1.0\powershell.exe `
-CommandLineTemplate " -command `"C:\Scripts\Test.ps1 %TargetInstance% >>C:\Scripts\test.out`""
#Bind filter to the consumer
New-WmiFilterToConsumerBinding -Filter $Filter -Consumer $Consumer –Verbose 

• Created simple blocking condition within SQL Server using the following two scripts (in separate SSMS windows of course)... (note: if you're following this, it can be easily duplicated using whatever database/table you like)

--Execute this in 1st window (this creates exclusive lock on table given that it's within a transaction)
begin tran

update tbl set textdata = '' 
from [dbo].[RIC1PDWSWSQL01_20120227] tbl
where textdata is null

--To stop testing... rollback
--rollback

--Execute this in 2nd window (this session will be blocked by the update statement within an open tran)
select * from [dbo].[RIC1PDWSWSQL01_20120227] tbl

• Confirmed via wmieventhelper.exe that the permanent event was configured

• Confirmed blocking condition was triggering the WMI event via using wbemtest.exe tool

• Could not see any events firing via the WMIExplorer.exe tool

But the test.ps1 script apparently never fires as I see no update to the test.out file.  I'm not sure if there's an error (don't see any via any of the WMI exploration tools mentioned) and, again, I tested it to ensure there would be no issues.  I feared that the issue may be the reference to the %TargetInstance% WMI token but that shouldn't keep test.ps1 from running and at least outputting an error (or a null parameter passed).

Any help would be appreciated.

Thanks,

Raul