Home
All Oracle Error Codes
Oracle DBA Forum

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

[suse-oracle] Total System Global Area size.

Robert Scheckle

2005-11-04

Replies:
Hi;



Does the TOTAL SGA size have a 2GB limit on Linux?



I had the following scary scenario on my production system last night.



After studying a stats pack report I altered the db_cache_size
parameter.



The original settings were:

*.pga_aggregate_target =  314572800           -> 300M

*.shared_pool_size     =  268435456           -> 256M

*.db_cache_size        =  956301312          -> 912M



Total System Global Area 1360599528 bytes     -> ~ 1297M

Fixed Size                       453096 bytes -> ~ 442K

Variable Size                402653184 bytes   ->   384M

Database Buffers           956301312 bytes    ->   912M

Redo Buffers                   1191936 bytes   -> ~   1M



I altered the *.db_cache_size        to 1509949440
-> 1440M

Using the following command.

ALTER SYSTEM SET db_cache_size=1440M SCOPE=spfile SID='*';



I then stopped and started the database with the following result.

SQL> startup

ORA-27123: unable to attach to shared memory segment

Linux Error: 22: Invalid argument

Additional information: 1

Additional information: 491520



I rolled back to my original settings and the database came up.



The new setting added 528M to the SGA making the TOTAL SGA 1297M + 528M
= 1825M.



The Database servers have 2 Databases each and 5GB RAM.



oracle@(protected)

-->free

        total     used     free   shared   buffers
cached

Mem:     4915008   1847668   3067340       0    38684
1110396

-/+ buffers/cache:   698588   4216420

Swap:    6291408   726124   5565284

oracle@(protected)



SuSE kernel is 2.4.21-251-smp



Regards;

Robert Scheckle
Database Administrator
______________________
Digicare Technologies

T: +27 (0)12 673 8595
M: +27 (0)83 399 1442
E: roberts@(protected)