oracle性能优化参数的调整

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1.SHARE_POOL_SIZE

数据字典的命中率计算:
select ((1 - (Sum(GetMisses) / (Sum(Gets) + Sum(GetMisses)))) * 100) "Hit Rate"
from V$RowCache
where Gets + GetMisses <> 0;
数据字典的命中率低于95%可考虑提升SHARE_POOL_SIZE

 

LIBRARY CACHE(reload)的命中率计算:

select Sum(Pins) "Hits",
Sum(Reloads) "Misses",
((Sum(Reloads) / Sum(Pins)) * 100)"Reload %"
from V$LibraryCache;
LIBRARY CACHE的命中率计算:

select Sum(Pins) "Hits",
Sum(Reloads) "Misses",
Sum(Pins) / (Sum(Pins) + Sum(Reloads)) "Hit Ratio"
from V$LibraryCache;

LIBRARY CACHE(reload)的命中率高于1%或LIBRARY CACHE命中率低于95%可考虑增大SHARE_POOL_SIZE