hi,
some standard checks
SIFT
Swith off SumIndexFields for large tables, will remove vsift views but can improve performances reducing locks on large tables
COSTS RECALCULATION
If are you using "Automatic Adjust Cost" > swith off function, make a scheduled job (on NAS) to recalculate costs
REBUILD INDEXES
Rebuld indexes on SQL Server or optimize tables on NAV
TRACING SLAW CALLS
run the process with SQL Profiler or the NAV Client Monitor
trace locks & deadlocks
check pending sessions on sql server > if you have, you need more memory
