Unresolved Deadlock vs Scheduler Deadlock

Moved from: bobsql.com


These are distinct errors but I have found that many people blend them together.  It really takes an entire chapter to explain these conditions so I am going try to do it in a page or two?


Unresolved Deadlock

An unresolved deadlock is generally a SQL Server product issue.   When an unresolved deadlock is detected a message is added to the SQL Server error log and a mini-dump is captured.


The Lock Monitor is responsible for detecting and resolving deadlocks for SQL Server.   It does this by building a lock graph (you may have