ionice
Modern Linux introduced the
ionice
command to change disk I/O priority of a process.
I did carefully investigate the effect of ionice'd ORACLE RDBMS sessions on a heavy loaded multiprocessing 10gR2 system with filesystemio_options=setall using a number of SELECTs involving much disk I/O:
SQL> set timing on;
SQL> select count(*) from (select owner,segment_name,blocks from dba_extents order by 3);
Elapsed: 00:16:58.58
Experiments show that varying the prioroty of server-side process from IDLE to REALTIME does not affect noticeable the time the above select runs.
This strange result disappoidted me using ionice with ORACLE.
Does anibody else has different results?
I did carefully investigate the effect of ionice'd ORACLE RDBMS sessions on a heavy loaded multiprocessing 10gR2 system with filesystemio_options=setall using a number of SELECTs involving much disk I/O:
SQL> set timing on;
SQL> select count(*) from (select owner,segment_name,blocks from dba_extents order by 3);
Elapsed: 00:16:58.58
Experiments show that varying the prioroty of server-side process from IDLE to REALTIME does not affect noticeable the time the above select runs.
This strange result disappoidted me using ionice with ORACLE.
Does anibody else has different results?
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