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Frequent Oracle Errors

TNS:could not resolve the connect identifier specified
Backtrace message unwound by exceptions
invalid identifier
PL/SQL compilation error
internal error
missing expression
table or view does not exist
end-of-file on communication channel
TNS:listener unknown in connect descriptor
insufficient privileges
PL/SQL: numeric or value error string
TNS:protocol adapter error
ORACLE not available
target host or object does not exist
invalid number
unable to allocate string bytes of shared memory
resource busy and acquire with NOWAIT specified
error occurred at recursive SQL level string
ORACLE initialization or shutdown in progress
archiver error. Connect internal only, until freed
snapshot too old
unable to extend temp segment by string in tablespace
Credential retrieval failed
missing or invalid option
invalid username/password; logon denied
unable to create INITIAL extent for segment
out of process memory when trying to allocate string bytes
shared memory realm does not exist
cannot insert NULL
TNS:unable to connect to destination
remote database not found ora-02019
exception encountered: core dump
inconsistent datatypes
no data found
TNS:operation timed out
PL/SQL: could not find program
existing state of packages has been discarded
maximum number of processes exceeded
error signaled in parallel query server
ORACLE instance terminated. Disconnection forced
TNS:packet writer failure
see ORA-12699
missing right parenthesis
name is already used by an existing object
cannot identify/lock data file
invalid file operation
quoted string not properly terminated

RE: SGA rules of thumb?

Bobak, Mark


Hi Don,

This is tricky, and is really something that develops over time, as you
monitor the database performance and get an idea for where performance
suffers and what SGA components need tweaking. I don't think there are
any (valid) rules of thumb that can be applied. It would probably be
reasonable to use the ASMM sizes as a starting point. Then, monitor the
system. Look for any performance problems cropping up in your business
processes. If you see something not performing well, profile it. Use
that profile to tune, and to tell you where you need more resources in
your SGA allocation.


Mark J. Bobak
Senior Oracle Architect

"There are 10 types of people in the world: Those who understand
binary, and those who don't."

-----Original Message-----
From: oracle-l-bounce@(protected)
Sent: Monday, May 07, 2007 12:17 PM
To: oracle_l
Subject: SGA rules of thumb?

I'm wondering if any of you have general "rules of thumb" when it comes
to sizing the various pools and db buffer cache within the SGA.
I'm going to go back to static SGA rather than risk ASMM thrashing about
and causing another ORA-00600 at 2:30 in the morning. I can see where
ASMM left the sizes at last, but just wondering what human thinks of

This is Oracle on RHEL3. sga_max_size is 1456M on 32-bit,
going to be (at least) 8192M on 64-bit. The database is a hybrid of
OLTP and warehouse. When I say "warehouse", I mean that large
partitioned tables holding millions of records exist, and are bulk
loaded via external tables and data pump throughout the day. Other than
the bulk loading, those tables are read-only.

Any advice would be appreciated (yes I've checked the V$*_ADVICE views
as well).

Don Seiler
oracle blog: http://ora.seiler.us
ultimate: http://www.mufc.us