Take the 2-minute tour ×  Recently I have been struggling with
SQL server performance and although we have fixed a huge
multitude of basic errors in the config it is still performing
badly. To clarify it is not overall performance but rather
fairly frequent time outs (from the client application).
Previously I had looked to the memory as a cause but this has
now been resolved and we are still getting the same behaviour.
Looking at the graphs from Management Data Warehouse I can see
that LCK_M_U/X/IX are causing the majority of our waits around
the time a user experiences a timeout. Everything I am reading
states I need to look at the queries and processes running but I
have yet to find anything aimed at a level I can understand. The
locks, as you can see in the picture below, seem to spike which
coincides with the error on the users side. Is there a clever
DMV or some such that I can address to try and work out what
query is being run that is creating the lock? Is it a case of
trawling through a trace to fin