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Group,
I have the following query.
select a.*
from
golfowner.scott_match_data a,
(select * from golfowner.t_mtch_subj_id where rownum < 50) b
where a.wb_ctry_cd = 785
Using tkprof to collect waits for the above query I found that the read time is what is impacting performance of this query. I would like to know if these times are realistic for a lightly loaded server.
The database is a 2node RAC cluster running HP-UX 11.11 with raw partitions on a Symmetrix. Does my Symm need a check up or is there some setting I can change to increase the read IO. ( Async IO is already set up )
Thanks,
Scottt Watson.
select /* new */ a.*
from
golfowner.scott_match_data a,
(select * from golfowner.t_mtch_subj_id where rownum < :"SYS_B_0") b
where a.wb_ctry_cd = :"SYS_B_1"
call count cpu elapsed disk query current rows ------- ------ -------- ---------- ---------- ---------- ---------- ----------
Parse 1 0.00 0.00 0 0 0 0 Execute 1 0.00 0.00 0 0 0 0 Fetch 33 0.06 2.50 254 736 0 473 ------- ------ -------- ---------- ---------- ---------- ---------- ---------- total 35 0.06 2.50 254 736 0 473
Misses in library cache during parse: 1
Optimizer goal: FIRST_ROWS
Parsing user id: SYS
Rows Row Source Operation
------- ---------------------------------------------------
473 TABLE ACCESS BY INDEX ROWID SCOTT_MATCH_DATA (cr=736 r=254 w=0 time=2497285 us) 573 NESTED LOOPS (cr=299 r=36 w=0 time=239305 us)
99 VIEW (cr=36 r=0 w=0 time=660 us) 99 COUNT STOPKEY (cr=36 r=0 w=0 time=527 us) 99 TABLE ACCESS FULL T_MTCH_SUBJ_ID (cr=36 r=0 w=0 time=396 us)473 INDEX RANGE SCAN SCOTT_MATCH_DATA_IX01 (cr=263 r=36 w=0 time=237472 us)(object id 45838)
Elapsed times include waiting on following events:
Event waited on Times Max. Wait Total Waited ---------------------------------------- Waited ---------- ------------ SQL*Net message to client 33 0.00 0.00 global cache cr request 108 0.00 0.03 SQL*Net message from client 33 0.00 0.03 db file sequential read 254 0.45 2.42Received on Mon Oct 27 2003 - 16:29:29 CST