Init parameterRedo, undo & archiving

FAST_START_MTTR_TARGET

What it controls

Target seconds for crash recovery. Oracle writes dirty blocks early enough to meet it.

Know this before you change it

Lower values mean faster instance recovery but more background writes.

Default: 0

Check and change it

1-- Current value on every instance2SELECT inst_id, name, value, isdefault, ismodified3FROM gv$parameter4WHERE name = 'fast_start_mttr_target';5 6-- Value stored in the spfile7SELECT sid, value FROM v$spparameter WHERE name = 'fast_start_mttr_target' AND isspecified = 'TRUE';8 9-- Dynamic: takes effect now and is kept after a restart10ALTER SYSTEM SET fast_start_mttr_target = 300 SCOPE = BOTH SID = '*';11 12-- Remove it from the spfile to go back to the default at the next restart13ALTER SYSTEM RESET fast_start_mttr_target SCOPE = SPFILE SID = '*';

Open in the parameter referenceOracle's reference

More in Redo, undo & archiving

• UNDO_RETENTIONSeconds of committed undo Oracle tries to keep, for long queries and Flashback Query.
• UNDO_TABLESPACEWhich undo tablespace the instance uses. Each RAC instance has its own.
• LOG_ARCHIVE_DEST_NWhere archived redo goes: a local location or a Data Guard standby service. Numbered 1 to 31.
• LOG_ARCHIVE_FORMATFile name pattern for archived logs written to a plain directory.
• ARCHIVE_LAG_TARGETForces a log switch after this many seconds, even when the database is quiet.
• LOG_BUFFERSize of the redo log buffer.