要回答这个问题，您需要历史性能指标。获得这些的最简单方法是从 AWR 视图 DBA_HIST_SQLSTAT [需要许可证]（也可以使用 StatsPack）。至于获得一个百分比，您需要从总可用 CPU 中计算出来，但可能仅按 CPU 消耗排序就足够了。我从 AWR 表中使用的查询：
select ord ord
, case
when nvl(:order_by, 'GET') in ('ELAP' , '1') then 'elapsed_sec'
when nvl(:order_by, 'GET') in ('CPU' , '2') then 'cpu_sec'
when nvl(:order_by, 'GET') in ('IO' , '3') then 'iowait'
when nvl(:order_by, 'GET') in ('GET' , '4') then 'buffer_gets'
when nvl(:order_by, 'GET') in ('READ' , '5') then 'disk_reads'
when nvl(:order_by, 'GET') in ('EXEC' , '6') then 'executions'
when nvl(:order_by, 'GET') in ('PARSE', '7') then 'parse_calls'
when nvl(:order_by, 'GET') in ('MEM' , '8') then 'sharable_mem'
when nvl(:order_by, 'GET') in ('VERS' , '9') then 'version_count'
when nvl(:order_by, 'GET') in ('ELAP_EXEC' , '10') then 'time_per_exec'
when nvl(:order_by, 'GET') in ('SNAP' , '11') then 'snap_id'
else 'buffer_gets'
end order_by
, schema
, sql_id
, plan_hash_value "Plan Hash Value"
, (select
max(to_number(extractvalue(
xmltype(other_xml),'other_xml/info[@type="plan_hash_2"]'))) plan_hash_2
from dba_hist_sql_plan hp
where hp.sql_id = main_query.sql_id
and hp.plan_hash_value = main_query.plan_hash_value
and hp.other_xml is not null) plan_hash_2
, (select max(last_refresh_time) from gv$sql_monitor sm where sm.sql_id = main_query.sql_id and sm.sql_plan_hash_value = main_query.plan_hash_value) monitor_last_refresh_time
, time_per_exec "Time Per Exec"
, executions "Exec-utions"
, clock_time "Clock Time"
, px_servers_execs "px servers execs"
, sql_text
, buffer_gets "Buffer Gets"
, fetches
, rows_processed "rows processed"
, round(rows_processed / nullif(fetches, 0)) "rows per fetch"
, end_of_fetch_count "end of fetch count"
, sorts
, disk_reads "disk reads"
, tot_wait "Tot Wait"
, iowait
, clwait
, apwait
, ccwait
, direct_writes "direct writes"
, elapsed_sec "Elap-sed (Sec)"
, cpu_sec "CPU Sec"
, plsql_sec "PL/SQL sec"
, plsexec_time "pls exec time"
, javexec_time "java exec time"
, sharable_mem "shar-able mem"
-- per exec calculations
, case when executions > 0 then buffer_gets/executions else 0 end "Buffer Gets per exec"
, case when executions > 0 then fetches/executions else 0 end "Fetches Gets per exec"
, case when executions > 0 then rows_processed/executions else 0 end "rows per exec"
, case when executions > 0 then sorts/executions else 0 end "sorts per exec"
, case when executions > 0 then disk_reads/executions else 0 end "disk reads per exec"
, case when executions > 0 then tot_wait/executions else 0 end "Tot Wait per exec"
, case when executions > 0 then iowait/executions else 0 end "iowait per exec"
, case when executions > 0 then clwait/executions else 0 end "clwait per exec"
, case when executions > 0 then apwait/executions else 0 end "apwait per exec"
, case when executions > 0 then ccwait/executions else 0 end "ccwait per exec"
, case when executions > 0 then direct_writes/executions else 0 end "direct writes per exec"
, case when executions > 0 then elapsed_sec/executions else 0 end "Elap-sed (Sec) per exec"
, case when executions > 0 then cpu_sec/executions else 0 end "CPU Sec per exec"
, case when executions > 0 then plsql_sec/executions else 0 end "PL/SQL sec per exec"
, case when executions > 0 then plsexec_time/executions else 0 end "pls exec time per exec"
, case when executions > 0 then javexec_time/executions else 0 end "java exec time per exec"
, case when executions > 0 then sharable_mem/executions else 0 end "shar-able mem per exec"
-- per row calculations
, case when rows_processed > 0 then buffer_gets/rows_processed else 0 end "Buffer Gets per row"
, case when rows_processed > 0 then fetches/rows_processed else 0 end "Fetches Gets per row"
, case when rows_processed > 0 then rows_processed/rows_processed else 0 end "rows per row"
, case when rows_processed > 0 then sorts/rows_processed else 0 end "sorts per row"
, case when rows_processed > 0 then disk_reads/rows_processed else 0 end "disk reads per row"
, case when rows_processed > 0 then tot_wait/rows_processed else 0 end "Tot Wait per row"
, case when rows_processed > 0 then iowait/rows_processed else 0 end "iowait per row"
, case when rows_processed > 0 then clwait/rows_processed else 0 end "clwait per row"
, case when rows_processed > 0 then apwait/rows_processed else 0 end "apwait per row"
, case when rows_processed > 0 then ccwait/rows_processed else 0 end "ccwait per row"
, case when rows_processed > 0 then direct_writes/rows_processed else 0 end "direct writes per row"
, case when rows_processed > 0 then elapsed_sec/rows_processed else 0 end "Elap-sed (Sec) per row"
, case when rows_processed > 0 then cpu_sec/rows_processed else 0 end "CPU Sec per row"
, case when rows_processed > 0 then plsql_sec/rows_processed else 0 end "PL/SQL sec per row"
, case when rows_processed > 0 then plsexec_time/rows_processed else 0 end "pls exec time per row"
, case when rows_processed > 0 then javexec_time/rows_processed else 0 end "java exec time per row"
, case when rows_processed > 0 then sharable_mem/rows_processed else 0 end "shar-able mem per row"
, loaded_versions "loaded vers-ions"
, version_count "ver-sion count"
, loads
, invalidations "invalid-ations"
, parse_calls "parse calls"
, module
, command_type_name
, to_char(min_time, 'mm/dd/yyyy HH24:MI:SS') min_time
, to_char(max_time ,'mm/dd/yyyy HH24:MI:SS') max_time
, min_snap_id "Min Snap Id"
, max_snap_id "Max Snap Id"
, sql_profile
, Baseline_plan_name -- does not work for 10g
from
(
select schema
, plan_hash_value
, sql_id
, rownum ord
, sub.elapsed_sec
, CASE
WHEN elapsed_sec > 86399
THEN elapsed_sec || ' sec'
WHEN elapsed_sec <= 86399
THEN to_char(to_date(round(elapsed_sec) ,'SSSSS'), 'HH24:MI:SS')
END as clock_time
, case when executions <> 0
then CASE
WHEN round(elapsed_sec/(executions*decode(px_servers_execs, 0, 1, px_servers_execs))) > 86399
THEN round(elapsed_sec/(executions)*decode(px_servers_execs, 0, 1, px_servers_execs)) || ' sec'
WHEN round(elapsed_sec/(executions*decode(px_servers_execs, 0, 1, px_servers_execs))) <= 86399
THEN to_char(to_date(round(elapsed_sec/(executions*decode(px_servers_execs, 0, 1, px_servers_execs))) ,'SSSSS'), 'HH24:MI:SS')
END
end as time_per_exec
, cpu_sec
, plsql_sec
, executions
, buffer_gets
, sharable_mem
, loaded_versions
, version_count
, module
, fetches
, end_of_fetch_count
, sorts
, px_servers_execs
, loads
, invalidations
, parse_calls
, disk_reads
, rows_processed
, iowait
, clwait
, apwait
, ccwait
, tot_wait
, direct_writes
, plsexec_time
, javexec_time
, (select max(DBMS_LOB.SUBSTR(sql_text, 3800)) from dba_hist_sqltext st where st.sql_id = sub.sql_id) sql_text
, (select max(name) from dba_hist_sqltext st, audit_actions aa where st.sql_id = sub.sql_id and aa.action = st.command_type) command_type_name
, min_time
, max_time
, min_snap_id
, max_snap_id
, sql_profile
, (select nvl(min(sql_plan_baseline), 'none') from v$sql sql where sql.sql_id = sub.sql_id and sql.plan_hash_value = sub.plan_hash_value) Baseline_plan_name -- does not work for 10g
from
( -- sub to sort before rownum
select
sql_id
, plan_hash_value
, round(sum(elapsed_time_delta)/1000000) as elapsed_sec
, round(sum(cpu_time_delta) /1000000) as cpu_sec
, round(sum(plsexec_time_delta)/1000000) as plsql_sec
, sum(executions_delta) as executions
, sum(buffer_gets_delta) as buffer_gets
, sum(sharable_mem) as sharable_mem
, sum(loaded_versions) as loaded_versions
, sum(version_count) as version_count
, max(module) as module
, sum(fetches_delta) as fetches
, sum(end_of_fetch_count_delta) as end_of_fetch_count
, sum(sorts_delta) as sorts
, sum(px_servers_execs_delta) as px_servers_execs
, sum(loads_delta) as loads
, sum(invalidations_delta) as invalidations
, sum(parse_calls_delta) as parse_calls
, sum(disk_reads_delta) as disk_reads
, sum(rows_processed_delta) as rows_processed
, sum(iowait_delta) as iowait
, sum(clwait_delta) as clwait
, sum(apwait_delta) as apwait
, sum(ccwait_delta) as ccwait
, sum(iowait_delta) + sum(clwait_delta) + sum(apwait_delta) + sum(ccwait_delta) as tot_wait
, sum(direct_writes_delta) as direct_writes
, sum(plsexec_time_delta) as plsexec_time
, sum(javexec_time_delta) as javexec_time
, max(parsing_schema_name) as schema
, max(snap.end_INTERVAL_TIME) max_time
, min(snap.end_INTERVAL_TIME) min_time
, min(stat.snap_id) min_snap_id
, max(stat.snap_id) max_snap_id
, min(nvl(sql_profile, 'none')) sql_profile
from
dba_hist_snapshot snap
, dba_hist_sqlstat stat
where 1=1
and nvl(:order_by, 'GET') like '%'
and snap.dbid = stat.dbid
and snap.instance_number = stat.instance_number
and snap.snap_id = stat.snap_id
and snap.snap_id between nvl(:start_snap_id, snap.snap_id) and nvl(:end_snap_id, snap.snap_id)
and nvl(parsing_schema_name,'%') like nvl(upper(:username), nvl(parsing_schema_name,'%') )
and sql_id = nvl(:sql_id, sql_id)
and nvl(plan_hash_value,0) = nvl(:plan_hash_value, nvl(plan_hash_value,0))
and nvl(module,'x') like nvl(:module, nvl(module,'x'))
and stat.instance_number = nvl(:inst_id, stat.instance_number)
and decode(:days_back_only_Y_N,'Y', end_INTERVAL_TIME, trunc(sysdate-:days_back) ) >= trunc(sysdate-:days_back)
and (trunc(begin_INTERVAL_TIME, 'MI') >= to_date(nvl(:sam_tm_str_MM_DD_YYYY_HH24_MI, to_char(begin_interval_time, 'MM_DD_YYYY_HH24_MI')),'MM_DD_YYYY_HH24_MI')
and trunc(end_interval_time, 'MI') <= to_date(nvl(:sam_tm_end_MM_DD_YYYY_HH24_MI, to_char(end_interval_time, 'MM_DD_YYYY_HH24_MI')),'MM_DD_YYYY_HH24_MI'))
and (to_number(to_char(begin_INTERVAL_TIME, 'HH24')) between nvl(:begin_hour, 0) and nvl(:end_hour, 24)
or to_number(to_char(begin_INTERVAL_TIME, 'HH24')) between nvl(:begin_hour2, nvl(:begin_hour, 0)) and nvl(:end_hour2, nvl(:end_hour, 24)))
group by sql_id, plan_hash_value --, force_matching_signature -- , stat.instance_number
order by
case
when nvl(:order_by, 'GET') in ('ELAP' , '1') then elapsed_sec
when nvl(:order_by, 'GET') in ('CPU' , '2') then cpu_sec
when nvl(:order_by, 'GET') in ('IO' , '3') then iowait
when nvl(:order_by, 'GET') in ('GET' , '4') then buffer_gets
when nvl(:order_by, 'GET') in ('READ' , '5') then disk_reads
when nvl(:order_by, 'GET') in ('EXEC' , '6') then executions
when nvl(:order_by, 'GET') in ('PARSE', '7') then parse_calls
when nvl(:order_by, 'GET') in ('MEM' , '8') then sharable_mem
when nvl(:order_by, 'GET') in ('VERS' , '9') then version_count
when nvl(:order_by, 'GET') in ('ELAP_EXEC' , '10') then case when executions <> 0 then elapsed_sec/(executions*decode(px_servers_execs, 0, 1, px_servers_execs)) else elapsed_sec end
when nvl(:order_by, 'GET') in ('SNAP' , '11') then min_snap_id
else buffer_gets
end desc
) sub
where 1=1
and rownum <= :top_n
) main_query
where 1=1
and nvl(upper(sql_text), '%') like nvl(upper(:sql_text), '%')
and nvl(command_type_name, 'x') like nvl(:command_type_name, nvl(command_type_name, 'x'))
order by
case
when nvl(:order_by, 'GET') in ('ELAP' , '1') then elapsed_sec
when nvl(:order_by, 'GET') in ('CPU' , '2') then cpu_sec
when nvl(:order_by, 'GET') in ('IO' , '3') then iowait
when nvl(:order_by, 'GET') in ('GET' , '4') then buffer_gets -- essentially an overall workload ordering
when nvl(:order_by, 'GET') in ('READ' , '5') then disk_reads
when nvl(:order_by, 'GET') in ('EXEC' , '6') then executions
when nvl(:order_by, 'GET') in ('PARSE', '7') then parse_calls
when nvl(:order_by, 'GET') in ('MEM' , '8') then sharable_mem
when nvl(:order_by, 'GET') in ('VERS' , '9') then version_count
when nvl(:order_by, 'GET') in ('ELAP_EXEC' , '10') then case when executions <> 0 then elapsed_sec/(executions*decode(px_servers_execs, 0, 1, px_servers_execs)) else elapsed_sec end
when nvl(:order_by, 'GET') in ('SNAP' , '11') then min_snap_id
else buffer_gets
end desc
;