title: SQL Server lock escalation issue
body: <p>I am reading SQL Server lock escalation from <a href="http://msdn.microsoft.com/en-us/library/aa213033(SQL.80).aspx" rel="noreferrer">MSDN Page about SQL Server lock escalation</a></p>
  
  <p>My question is, seems the major reason why there is lock escalation is to reduce overhead to maintain more locks (e.g. when more row locks are acquired for a table, then row level lock is escalated to table level). My question is, to maintain more locks will improve concurrency, it is a benefit, why it is an overhead? In my humble idea, lock should be as small as enough to make the db performance better by improving concurrency. Could anyone explain in simple way why lock escalation is needed and what is the so-called lock overhead please?</p>
  
  <p>thanks in advance,
  George</p>