I'm having some issues with a slow performing 6.1.6 site. The bottleneck seems to be SQL server. Sounds a bit similar to this thread: http://our.umbraco.org/forum/ourumb-dev-forum/bugs/45034-Performance-issues-database-locks-since-612

Lots of locks and timeouts when more than one editor is using the system, and the logs are full of:

2013-12-24 09:37:46,291 [9] INFO  Umbraco.Core.Persistence.UmbracoDatabase - [Thread 70]    at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction)

   at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose)

   at System.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady)

   at System.Data.SqlClient.SqlDataReader.TryHasMoreRows(Boolean& moreRows)

   at System.Data.SqlClient.SqlDataReader.TryReadInternal(Boolean setTimeout, Boolean& more)

   at System.Data.SqlClient.SqlDataReader.Read()

   at Umbraco.Core.Persistence.Database.<Query>d__1c`1.MoveNext()

Anyone got any suggestions?