You may need to read through the documentation on the Pipeline Execute snap as it isn’t exactly a replacement of the Task Execute.
https://docs-snaplogic.atlassian.net/wiki/spaces/SD/pages/1438684/Pipeline+Execute
The deadlock behavior you are experiencing is not related to the Pipeline Execute. This is a database deadlock, so it is related to how the update statement is being executed. You may wish to use “Validate Pipeline” to view the documents as they are being passed to the child and determine if the child will process the records appropriately.
Also remember that by enabling “reuse executions” on the Pipeline Execute, the pipeline parameters passed to the child are only evaluated on the first document, which I believe is different from the Task Execute behavior.
