V$LICENSE

V$LICENSE displays information about license limits.

Column	Datatype	Description
SESSIONS_MAX	NUMBER	Maximum number of concurrent user sessions allowed for the instance
SESSIONS_WARNING	NUMBER	Warning limit for concurrent user sessions for the instance
SESSIONS_CURRENT	NUMBER	Current number of concurrent user sessions
SESSIONS_HIGHWATER	NUMBER	Highest number of concurrent user sessions since the instance started
USERS_MAX	NUMBER	Maximum number of named users allowed for the database
CPU_COUNT_CURRENT	NUMBER	Current number of logical CPUs or processors on the system
CPU_CORE_COUNT_CURRENT	NUMBER	Current number of CPU cores on the system (includes subcores of multicore CPUs, as well as single-core CPUs)
CPU_SOCKET_COUNT_CURRENT	NUMBER	Current number of CPU sockets on the system (represents an absolute count of CPU chips on the system, regardless of multithreading or multicore architectures)
CPU_COUNT_HIGHWATER	NUMBER	Highest number of logical CPUs or processors on the system since the instance started
CPU_CORE_COUNT_HIGHWATER	NUMBER	Highest number of CPU cores on the system since the instance started (includes subcores of multicore CPUs, as well as single-core CPUs)
CPU_SOCKET_COUNT_HIGHWATER	NUMBER	Highest number of CPU sockets on the system since the instance started (represents an absolute count of CPU chips on the system, regardless of multithreading or multicore architectures)

Note:

1. The availability of the CPU core count and CPU socket count statistics is subject to the operating system platform on which the Oracle Database is running. If a statistic is unavailable, the view will return NULL for the statistic value.
2. License usage in the database

SELECT sessions_current, sessions_highwater,        (select value from V$SYSSTAT where name = 'logons cumulative') cumulative_logins FROM   V$LICENSE;

SELECT rpad(c.name||':',11) || rpad(' current logons=' ||        (to_number(b.sessions_current)),20) || 'cumulative logons=' ||        rpad(substr(a.value,1,10),10) || 'highwater mark=' || b.sessions_highwater ||        '   startup time=' || to_char(d.startup_time,'YYYY/MM/DD HH24:MI:SS') Information FROM   V$SYSSTAT a, V$LICENSE b, V$DATABASE c, V$INSTANCE d WHERE  a.name = 'logons cumulative';

SELECT sessions_max, sessions_warning, sessions_current, sessions_highwater, users_max FROM   V$LICENSE;

3.       v$license and v$session

·    Session_highwater is derived from session_current, because if session_current is greater than session_highwater then session_highwater is set to session_current.

·    v$license and v$session are derived from the same sources.

·    Oracle background processes are included in v$session, but not in v$license. SNP processes are an exception to this rule.

4. Oracle errors

ORA-00018: maximum number of sessions exceeded Cause: You tried to execute a statement that requested a resource. Since the maximum number of sessions has been reached, Oracle will not process any new resource requests. Action: The options to resolve this Oracle error are: 1.        You can wait a few minutes and try to re-execute the statement(s). 2.        You can shut down Oracle, increase the SESSIONS parameter in the initialization parameter file, and restart Oracle.

Last updated: October 5, 2009 Monday

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