Redeploying SSIS packages - Cache? - ssis

Question

We have noticed an issue recently that redeployed SSIS packages sometime don't seem to include the latest changes... When I search the dtsx using notepad I see the amended script in the code so the changes are definitely there.
My assumption was that script components of SSIS packages are eventually compiled into an assembly somewhere in the process - this is quite likely since I would imagine C# code cannot run without something compiling it first. So in theory if these assemblies would then end up being cached and not immediately overwritten (for some reason) that would explain this issue.
The only "evidence" that makes me think that my theory is correct is if I keep running the package at some point it suddenly shifts to the new code.
However, so far I haven't found why and how this is happening, if is... Can anybody help?
UPDATE:
MSDN says: "Unlike earlier versions where you could indicate whether the scripts were precompiled, all scripts are precompiled in SQL Server 2008 Integration Services (SSIS) and later versions." - If by pre-compiled they mean that instead of the actual package a pre-compiled version runs (I think this because the package itself does not seem to be compiled since the code is visible in Notepad) there must be a way to force the engine to overwrite the pre-compiled assembly... but how?
UPDATE:
One of the four core components of SSIS is the SQL ServerIntegration Services service, which is a windows service. Apparently this service will cache component/task metadata so that the SSIS runtime engine can poll the cache to see what is installed, which may help speed up package load times. However, if the packages are stored in the file system (not in SQL Integration Services) and executed by Agent Jobs, the agent job will use the 64 bit version of DTEXEC to execute the packages. I haven't yet found evidence that any caching would be involved there, but there are certainly options to check a number of parameters in the validation phase of the execution, such as version numbers - may be for a reason.

Answer 1

Have you looked at sysssispackages to compare the version build number of the package in msdb to your build number in Visual Studio / SSIS?
SELECT name, verbuild
FROM msdb.dbo.sysssispackages
WHERE name LIKE '%bla%'
(Adjust WHERE-clause as necessary to find your package. Do NOT ever "SELECT * FROM msdb.dbo.sysssispackages" as it contains the package XML in one of the columns.)
And in Visual Studio, open the package, then right-click at the background of the package and select "Properties" from the context menu. Look at the field VersionBuild. It should match the number from the SELECT above!
I know this is not an actual solution to your problem but it may help locate where the cause of the problem is. If the number is older, it means that your package deployment did not work.

Answer 2

This sounds somewhat familiar to something I ran into a while back. Unfortunately, I don't remember exactly when I ran into this (so I can't check for sure), but I believe the fix I found was to make sure that I explicitly invoked the Build | Build st_5bd541c294054c25b9e7eb55b92bd0e2 command from the script editor (VSTA) menu before closing the window. (The specific project name will be different for each script, obviously, since it's based on a GUID; however, there will only be one possible submenu under Build.)
Explicitly invoking the Build command ensures that the binary code for the script gets ASCII-encoded and saved in the XML of the resulting .dtsx file. I'd gotten used to SSIS 2005 always building for me whenever I closed the script editor. Apparently, there are bizarre edge cases where SSIS 2008 doesn't always build the script project when the editor closes.
BTW, the precompiled binaries appear to be stored in a tag of the source XML called BinaryItem:
<DTS:Executable DTS:ExecutableType="Microsoft.SqlServer.Dts.Tasks.ScriptTask.ScriptTask, Microsoft.SqlServer.ScriptTask, Version=10.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91" DTS:ThreadHint="0">
<DTS:Property DTS:Name="ObjectName">SCR_StepOne</DTS:Property>
<DTS:ObjectData>
<ScriptProject Name="ST_5bd541c294054c25b9e7eb55b92bd0e2" VSTAMajorVersion="2" VSTAMinorVersion="1" Language="CSharp" EntryPoint="Main" ReadOnlyVariables="User::FileOneName,User::OutputFolder" ReadWriteVariables="">
<BinaryItem Name="\bin\release\st_5bd541c294054c25b9e7eb55b92bd0e2.csproj.dll">
TVqQAAMAAAAEAAAA//8AALgAAAAAAAAAQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAgAAAAA4fug4AtAnNIbgBTM0hVGhpcyBwcm9ncmFtIGNhbm5vdCBiZSBydW4gaW4gRE9TIG1v
ZGUuDQ0KJAAAAAAAAABQRQAATAEDADuOb04AAAAAAAAAAOAAAiELAQgAABAAAAAIAAAAAAAAPi8A
AAAgAAAAQAAAAABAAAAgAAAAAgAABAAAAAAAAAAEAAAAAAAAAACAAAAAAgAAAAAAAAMAQIUAABAA
It might be worth checking your source code control system history to see if that was getting updated for some of those screwy errors.
Caveat: I haven't found official Microsoft documentation on this.

Answer 3

This doesn't specifically solve the mystery you have, but if you are running file system-based packages and want to verify that the package that is running is the package you deployed, there is a way to do that.
Build your package.
Open the properties on your package and note down the "Version Build" property (alternatively, open the .dtsx in notepad and find the DTS:VersionBuild attribute.)
Deploy your package.
In your SQL Agent job step, go to the Verification tab.
Enter the Version Build in the "Verify package build" input box.
Execute the job step.
I don't know if this will force SSIS to throw out its cache and get the newly deployed package, but I do know if you modify the .dtsx package's build number by hand and then try to re-run the job step it fails because the package build doesn't match what it's looking for so it is definitely doing a run-time check of that value.