Smon process busy & lockwait for a session

Question

Hi when i am trying to archive some records using utl_file
the job seems haning.Whether it is really hanging.When i checked with the os process(oracle 8.1.7 on solaris 8)
its showing smon is busy.What exactly happening inside.I shtudown the database using shutdown abort last time becasue shutdown immediate was not working.Now its around 6 hours already the smon seems busy.why smon is so busy these much time.When i checked the the particualar session.It is showing lockwait in v$session for that archivng session.Why it is showing lockwait
with regards
ramya

Answer 1

Hi,
PCT_INCREASE=0 disabled smon coalesce.
From Metalink note 61997.1 :
SMON wakes itself every 5 minutes and checks for tablespaces with default pctincrease != 0.
Where to Set PCT_INCREASE=0 , if you are saying to change it for every segment in the database.. that’s not the good thing to do.I don't understand why pctincrease=0 on all objects is not a good idea.
Please read Metalink note 298696.1 (Fragmentation Issues Due to PCT_INCREASE Settings), where we can read :
Previously it was also believed that an object consisting of one large extent could be accessed quicker than an object of equal size, but composed of lot of smaller extents. Hence they preferred an object to consist of small number of very large extents, which was achieved by higher PCT_INCREASE values.
Today, we can add unlimited number of extents by setting MAXEXTENTS to UNLIMITED and the disk I/O performance is also significantly improved so we can manage with lot of small extents. So the benefit of setting larger PCT_INCREASE values has now become negligible.
Read this note, it's a very things.
Nicolas.