ORACLE?????????

????CPU?????????
????CPU?????????????????????????????????????????????CPU???????90?????????????????CPU???????90???????????????????CPU????????????????CPU?????????????????????CPU???????????
??????ò????????????????CPU?????????????UNIX??????????????????????sar–u?????CPU????????NT??????????????????????NT???????????????CPU????????
??????????????????????v$sysstat??select*fromv$sysstat wherenamelike'CPU%'???????????“CPUused by this session”???????ORACLE?????????CPU?????“OS Userlevel CPU time“???????????????????CPU?????“OS Systemcall CPU time“?????????????????μ?CPU????????????CPU????????????????????????ORACLE?????????CPU?????????????CPU???90????????????????CPU???????ORACLE?????????????????????????????????CPU????????????ù???ORACLE????????????????CPU???
????????????????????????v$sesstat??????????????????ORACLE??????????????CPU????????????????÷?????CPU??????select*fromv$sysstat orderbyvaluedesc??
????????CPU?????????????????SQL?????????????Ч???SQL????????????????CPU???????
????1?????????????????????????????SQL????????????
????SELECT * FROM V$SYSSTAT
????WHERE NAME IN
????('parse time cpu'?? 'parse time elapsed'?? 'parse count (hard)');
????????parse time cpu???????????parse timeelapsed?????????????????
????waite time = parse time elapsed – parse time cpu
???????????????SQL????????????????waite time / parse count????????????????y????0??????????????????????????????????????????????
????SELECTSQL_TEXT?? PARSE_CALLS?? EXECUTIONS FROM V$SQLAREA
????ORDER BY PARSE_CALLS;
??????????????SQL??????Ч????????????????????Щ???????????ORACLE????SESSION_CACHED_CURSORS?????
????2???????????????????????????
????SELECT BUFFER_GETS?? EXECUTIONS?? SQL_TEXT FROMV$SQLAREA;
????????Ч???SQL????????Щ?????????????CPU?????????
????3??????????????????v$system_event??select*fromv$system_event where event like'_atch%';??????????е?”latchfree“??????ORACLE??????????????????г???????latch free?????????н?????????????????????????????????spin_count????????????????CPU??????