Had a weird situation for a few days where all update or delete requests to the FIM portal were timing out–but retrieving data worked just fine.

Running this command against the FIMService DB seems to have helped:

exec sp_updatestats ‘resample’

Several sites led me to the solution here: http://social.msdn.microsoft.com/Forums/sqlserver/en-US/f0692fe1-f2e1-4cb9-9fdb-0cf27077bc39/update-stats-with-full-scan-on-database