2.3.9 Oracle 10g automatic checkpoint adjustment (2.3.7 fast_start_mttr_target sequent)

 

Select name, value from V $ sysstat where upper (name) like '% dbwr % ';
SQL>/

NAME value
--------------------------------------------------------------------------
Flash cache insert SKIP: dbwr overloaded 0
Dbwr checkpoint buffers written 61031854
Dbwr thread checkpoint buffers written 53
Dbwr tablespace checkpoint Buffers' written 34559
Dbwr parallel query checkpoint buffers written 0
Dbwr object drop buffers written 10
Dbwr transaction table writes 302348
Dbwr undo block writes 11185035
Dbwr revisited being-written buffer 0
Dbwr LRU scans 0
Dbwr checkpointts 2432

NAME value
--------------------------------------------------------------------------
Dbwr fusion writes 29391272

12 rows selected.

SQL> select distinct REIO,
2 target_mttr tmttr,
3 estimated_mttr emttr,
4 writes_mttr wmttr,
5 writes_other_settings woset,
6 ckpt_block_writes ckptbw,
7 writes_autotune wauto,
8 writes_full_thread_ckpt wftckpt
9 from V $ instance_recovery;

REIO tmttr emttr wmttr woset ckptbw wauto
----------------------------------------------------------------------
Wftckpt
----------
118839 0 86 0 0 21042726 60997480
0

SQL> select 61031854-34559-60997480 from dual;

61031854-34559-60997480
-----------------------
-185

Writing a tablespace checkpoint is not completed by automatically adjusting the checkpoint. Oracle can write table space checkpoint events using fileq instead of ckptq.

Dbwr checkpoint buffers written = dbwr tablespace checkpoint buffers written + writes_autotune