Why same query takes different execution time in sql 2008

Hi!
With below query in SQL Server 2008 R2 when I change Book_ID to another value like '99000349' it takes very long time to execute while both result sets have same number of records!?
select Card_Serial,Asset_ID, Field_Name,Field_Value,Asset_Number,Field_ID,Book_ID from dbo.vw_InspectionReport where Book_ID='99000347'
I've test it more and more,A time I ran quickest one, or longest one first, restart Windows, but for some specific Book_ID values (although with same number of result set rows) it take multiple time slower than rest of Book_IDs.
Also showing state of the result set is different for these diffrent Book_IDs:
for fast ones it looks like below picture:
for slow ones it looks like below picture:
if you note, order of returned records are different!?
I'm waiting for your kindly reply!...

Do you see any changes if you add a hint to the query?
select Card_Serial,Asset_ID, Field_Name,Field_Value,Asset_Number,Field_ID,Book_ID from dbo.vw_InspectionReport where Book_ID='99000347OPTION(RECOMPILE)
Best Regards,Uri Dimant SQL Server MVP,
http://sqlblog.com/blogs/uri_dimant/
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Same query takes different time for two different users with same privileges

Hi,
Just wanted to know if it is possible for an INSERT query to take different amount of time for two different users for the same volume of data. If so, what could be the reason? I would like to add that we are not executing the query simultaneously. But it is always faster for user1(within 10-20 seconds) and slower for user2(takes around 8-10 minutes).

Show execution plan for each user. I think there is other reasons which you didn't not tell

Same query takes different time to fetch result from Database

Hi all,
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I tried analyzing that query in oracle, it recommended there are lots of hard parsing in that query.
Regards,

user10915512 wrote:
Hi all,
I am having a scenario in which a query is taking different time keeping other environmental variables constant.
When that query runs for 1 user it takes just 2 minutes to fetch result and the DB connection becomes inactive after fetching the result.
But if I run the same query after some time in similar environmentBut not exactly the same environment. So what is different that it is only "similar"?
it takes 25 minutes. sometimes 40 minutes to execute and give the result to the app server from the same database.
I am not able to understand this behavior from DB. Can anybody try to explain this behavior?Run a statspack on the 'well behaved' query and on the 'not well behaved' query. Compare and contrast the results.
>
The details of the DB are,
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
PL/SQL Release 11.2.0.1.0 - Production
CORE 11.2.0.1.0 Production
TNS for 32-bit Windows: Version 11.2.0.1.0 - Production
NLSRTL Version 11.2.0.1.0 - Production
OS Details:
Windows 2008 server Enterprise Edition. To paraphrase Forest Gump, "My momma always said Windows was like a box of chocolates ...."
>
>
I tried analyzing that query in oracle, it recommended there are lots of hard parsing in that query.
Regards,

Same query with different execution plan

Hello All,
I wonder why does sql server create different execution plan for these below queries ?
Thanks.

You can look at the expected query plan. Either visually in SSMS, or alternatively, you can run the query after the instruction SET SHOWPLAN_TEXT ON.
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In your particular case, the estimation for the second query is, that scanning just a small part of the nonclustered index and then looking up the table data of the qualifying rows is the cheapest approach, because the estimated number of qualifying rows
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TKPROF output below:
select count(*) from deal_bucket_detail where deal_bucket_id
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,     817
,     818
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and datetime between to_date('01-JUL-08','dd-MON-rr') and to_date('01-JAN-09','dd-MON-rr')
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        2      0.79       2.24       2936       3551          0           1
total        4      0.79       2.24       2936       3551          0           1
Misses in library cache during parse: 1
Optimizer mode: ALL_ROWS
Parsing user id: 43
Rows     Row Source Operation
      1 SORT AGGREGATE (cr=3551 pr=2936 pw=2936 time=0 us)
1430928   FILTER (cr=3551 pr=2936 pw=2936 time=380920 us)
1430928    INLIST ITERATOR (cr=3551 pr=2936 pw=2936 time=372057 us)
1430928     INDEX RANGE SCAN PK_DEAL_BUCKET_DETAIL (cr=3551 pr=2936 pw=2936 time=8782 us cost=1203 size=4069596 card=339133)(object id 14199)
Elapsed times include waiting on following events:
Event waited on                             Times   Max. Wait Total Waited
----------------------------------------   Waited ---------- ------------
SQL*Net message to client                       2        0.00          0.00
db file sequential read                      2936        0.02          1.49
SQL*Net message from client                     2        0.00          0.00
select count(*) from deal_bucket_detail where deal_bucket_id
between 815 and 997
and datetime between to_date('01-JUL-08','dd-MON-rr') and to_date('01-JAN-09','dd-MON-rr')
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        2      3.70       8.86      29199      26986          0           1
total        4      3.70       8.86      29199      26986          0           1
Misses in library cache during parse: 1
Optimizer mode: ALL_ROWS
Parsing user id: 43
Rows     Row Source Operation
      1 SORT AGGREGATE (cr=26986 pr=29199 pw=29199 time=0 us)
1430928   FILTER (cr=26986 pr=29199 pw=29199 time=6986078 us)
1430928    INDEX RANGE SCAN PK_DEAL_BUCKET_DETAIL (cr=26986 pr=29199 pw=29199 time=6977063 us cost=45208 size=5195748 card=432979)(object id 14199)
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Event waited on                             Times   Max. Wait Total Waited
----------------------------------------   Waited ---------- ------------
SQL*Net message to client                       2        0.00          0.00
db file sequential read                       219        0.04          0.08
db file parallel read                          35        0.04          0.32
db file scattered read                        211        0.10          5.02
SQL*Net message from client                     2        0.00          0.00
********************************************************************************How can I work out why the second query is doing much more work than the first?
Edited by: SamB on Aug 5, 2009 6:09 PM

Both are doing an index range scan, however a different index range scan.
query 1: inlist iterator with <n> index range scan for 1 value, due to hard-coded values.
query 2: index range scan for all values, starting at the lowest, due to between.
Sybrand Bakker
Senior Oracle DBA

Same sqlID with different execution plan and Elapsed Time (s), Executions time

Hello All,
The AWR reports for two days with same sqlID with different execution plan and Elapsed Time (s), Executions time please help me to find out what is reason for this change.
Please find the below detail 17th day my process are very slow as compare to 18th
17th Oct 18th Oct
221,808,602
21
2tc2d3u52rppt
213,170,100
72,495,618
9c8wqzz7kyf37
209,239,059
71,477,888
9c8wqzz7kyf37
139,331,777
1
7b0kzmf0pfpzn
144,813,295
1
0cqc3bxxd1yqy
102,045,818
1
8vp1ap3af0ma5
128,892,787
16,673,829
84cqfur5na6fg
89,485,065
1
5kk8nd3uzkw13
127,467,250
16,642,939
1uz87xssm312g
67,520,695
8,058,820
a9n705a9gfb71
104,490,582
12,443,376
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62,627,205
1
ctwjy8cs6vng2
101,677,382
15,147,771
3p8q3q0scmr2k
57,965,892
268,353
akp7vwtyfmuas
98,000,414
1
0ybdwg85v9v6m
57,519,802
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1kn9bv63xvjtc
87,293,909
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5kk8nd3uzkw13
52,690,398
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77,786,274
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1kn9bv63xvjtc
34,767,882
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bdgma0tn8ajz9
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Tablespace
Reads
Av Reads/s
Av Rd(ms)
Av Blks/Rd
Writes
Av Writes/s
Buffer Waits
Av Buf Wt(ms)
INDUS_TRN_DATA01
947,766
59
4.24
4.86
185,084
11
2,887
6.42
UNDOTBS2
517,609
32
4.27
1.00
112,070
7
108
11.85
INDUS_MST_DATA01
288,994
18
8.63
8.38
52,541
3
23,490
7.45
INDUS_TRN_INDX01
223,581
14
11.50
2.03
59,882
4
533
4.26
TEMP
198,936
12
2.77
17.88
11,179
1
732
2.13
INDUS_LOG_DATA01
45,838
3
4.81
14.36
348
0
1
0.00
INDUS_TMP_DATA01
44,020
3
4.41
16.55
244
0
1,587
4.79
SYSAUX
19,373
1
19.81
1.05
14,489
1
0
0.00
INDUS_LOG_INDX01
17,559
1
4.75
1.96
2,837
0
2
0.00
SYSTEM
7,881
0
12.15
1.04
1,361
0
109
7.71
INDUS_TMP_INDX01
1,873
0
11.48
13.62
231
0
0
0.00
INDUS_MST_INDX01
256
0
13.09
1.04
194
0
2
10.00
UNDOTBS1
70
0
1.86
1.00
60
0
0
0.00
STG_DATA01
63
0
1.27
1.00
60
0
0
0.00
USERS
63
0
0.32
1.00
60
0
0
0.00
INDUS_LOB_DATA01
62
0
0.32
1.00
60
0
0
0.00
TS_AUDIT
62
0
0.48
1.00
60
0
0
0.00
18th Oct
Tablespace
Reads
Av Reads/s
Av Rd(ms)
Av Blks/Rd
Writes
Av Writes/s
Buffer Waits
Av Buf Wt(ms)
INDUS_TRN_DATA01
980,283
91
1.40
4.74

The AWR reports for two days with same sqlID with different execution plan and Elapsed Time (s), Executions time please help me to find out what is reason for this change.
Please find the below detail 17th day my process are very slow as compare to 18th
You wrote with different execution plan, I think, you saw plans. It is very difficult, you get old plan.
I think Execution plans is not changed in different days, if you not added index or ...
What say ADDM report about this script?
As you know, It is normally, different Elapsed Time for same statement in different day.
It is depend your database workload.
It think you must use SQL Access and SQl Tuning advisor for this script.
You can get solution for slow running problem.
Regards
Mahir M. Quluzade

Different execution times for back ground jobs - why?

We have few jobs scheduled and each time they run, we see a different execution times. Some times, it increases and some times it decreases steeply . What could be the reasons?
Note:
1. We have the same load of jobs on the system in all the cases.
2. We haven't changed any settings at system level.
3. Data is more or less at the same range in all the executions.
4. We mainly run these jobs
Thanks,
Kiran
Edited by: kiran dasari on Mar 29, 2010 7:12 PM

Thank you Sandra.
We have no RFC calls or other instances. Ours is a very simple system. We have two monster jobs, the first one for HR dataand second an extract program to update a Z table for BW loads.
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Kiran

How query cost and execution time are releated ?

hi experts,
i am curious to know, how the query cost and execution time is related?
Query taking less time ,query cost is 65%, but query taking more time but query cost is 0%.
how to connect both and improve query performance.
Thanks

i think you are refering to cost (relative to the batch) execution 65%, where there are more that one statement, it may compare the cost of each statement with in the batch
i assume it mainly take subtree cost and IO stat as cost, but in some cases i may wrong when there is multi line function and many other facter influence the cost, and i would say it depends on the query
cost is unit-less
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chooses the one with the least cost. The cost tagged on each alternative is heurestically calculated, and is supposed to roughly reflect the amount of processing and I/O this alternative is going to take.
refer :
http://blogs.msdn.com/b/sqlqueryprocessing/archive/2006/10/11/what-is-this-cost.aspx
Thanks
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Different execution time

Hello, when i run the bellow code more than one time i am getting different execution time("Total time taken"),
Ex. when i run first time it prints Total time taken 47
second time it prints Total time taken 16
thrid time Total time taken 78 ,why its vary,
Please solve my question
long l = System.currentTimeMillis();
System.out.println(l);
     for(int i=0; i <88; i++){
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Its worth noting that the application is IO bound (due to printing to a device/console)
So you are really testing the performance of your IDE/console.
public static void main(String... args) throws IOException {
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Same query giving different results

Hi
I m surprised to see the behaviour of oracle. I have two different sessions for same scheema on same server. In both sessions same query returns different results. The query involves some calculations like sum and divisions on number field.
I have imported this data from another server using export / import utility available with 9i server. Before export every thing was going fine. Is there some problem with this utility.
I m using Developer 6i as the front end for my client server application. The behaviour of my application is very surprizing as once it shows the correct data and if I close the screen and reopen, it shows wrong data.
I m really stucked with the abnormal behaviour. Please tell me the possiblities and corrective action for these conditions.
Regards
Asad.

There is nothing uncommitted in both the sessions. But still different results are returned.
I m sending u the exact query and result returned in both sessions.
Session 1:
SQL> rollback;
Rollback complete.
SQL> SELECT CC.CREDIT_HRS,GP.GRADE_PTS
2 FROM GRADE G, COURSE_CODE CC, GRADE_POLICY GP
3 WHERE G.COURSE_CDE=CC.COURSE_CDE
4 AND G.SELECTION_ID=45 AND G.GRADE_TYP=GP.GRADE_TYP
5 AND G.TERM_PROG_ID=17 AND GP.TERM_ID=14
6 /
CREDIT_HRS GRADE_PTS
3 4
4 3.33
4 3.33
3 4
3 4
3 4
3 4
7 rows selected.
SQL>
SESSION 2:
SQL> rollback;
Rollback complete.
SQL> SELECT CC.CREDIT_HRS,GP.GRADE_PTS
2 FROM GRADE G, COURSE_CODE CC, GRADE_POLICY GP
3 WHERE G.COURSE_CDE=CC.COURSE_CDE
4 AND G.SELECTION_ID=45 AND G.GRADE_TYP=GP.GRADE_TYP
5 AND G.TERM_PROG_ID=17 AND GP.TERM_ID=14
6 /
CREDIT_HRS GRADE_PTS
3 4
4 3.33
3 4
3 4
3 4
3 4
6 rows selected.
SQL>
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Parsing the query takes too much time.

Hello.
I hitting the bug in в Oracle XE (parsing some query takes too much time).
A similar bug was previously found in the commercial release and was successfully fixed (SR Number 3-3301916511).
Please, raise a bug for Oracle XE.
Steps to reproduce the issue:
1. Extract files from testcase_dump.zip and testcase_sql.zip
2. Under username SYSTEM execute script schema.sql
3. Import data from file TESTCASE14.DMP
4. Under username SYSTEM execute script testcase14.sql
SQL text can be downloaded from http://files.mail.ru/DJTTE3
Datapump dump of testcase can be downloaded from http://files.mail.ru/EC1J36
Regards,
Viacheslav.

Bug number? Version fix applies to?
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Query takes a long time on EBAN table

Hi,
I am trying to execute a simple select statement on EBAN table. This query takes unexpectionally longer time to execute.
Query is :
SELECT banfn bnfpo ernam badat ebeln ebelp
      INTO TABLE gt_eban
      FROM eban FOR ALL ENTRIES IN gt_ekko_ekpo
      WHERE
      banfn IN s_banfn AND
      ernam IN s_ernam
      and ebeln = gt_ekko_ekpo-ebeln AND
      ebelp = gt_ekko_ekpo-ebelp.
Structure of gt_ekko_ekpo
TYPES : BEGIN OF ty_ekko_ekpo,
        ebeln TYPE ekko-ebeln,
        ebelp TYPE ekpo-ebelp,
        bukrs TYPE ekko-bukrs,
        aedat TYPE ekko-aedat,
        lifnr TYPE ekko-lifnr,
        ekorg TYPE ekko-ekorg,
        ekgrp TYPE ekko-ekgrp,
        waers TYPE ekko-waers,
        bedat TYPE ekko-bedat,
        otb_value TYPE ekko-otb_value,
        otb_res_value TYPE ekko-otb_res_value,
        matnr TYPE ekpo-matnr,
        werks TYPE ekpo-werks,
        matkl TYPE ekpo-matkl,
        elikz TYPE ekpo-elikz,
        wepos TYPE ekpo-wepos,
        emlif TYPE ekpo-emlif,
END OF ty_ekko_ekpo.
Structure of GT_EBAN
TYPES : BEGIN OF ty_eban,
banfn TYPE eban-banfn,
bnfpo TYPE eban-bnfpo,
ernam TYPE eban-ernam,
badat TYPE eban-badat,
ebeln TYPE eban-ebeln,
ebelp TYPE eban-ebelp,
END OF ty_eban.
Query seems to be OK to me. But still am not able to figure out the reason for this performance issue.
Please provide your inputs.
Thanks.
Richa

Hi Richa,
Maybe you are executing the query with S_BANFN empty. Still based on the note 191492 you should change your query on like the following
1st Suggestion:
if gt_ekko_ekpo[] is not initial.
SELECT banfn banfpo       INTO TABLE gt_eket
      FROM eket FOR ALL ENTRIES IN gt_ekko_ekpo
      WHERE
     ebeln = gt_ekko_ekpo-ebeln AND
      ebelp = gt_ekko_ekpo-ebelp.
if sy-subrc = 0.
delete gt_eket where banfn not in s_banfn.
if gt_eket[] is not initial
SELECT banfn bnfpo ernam badat ebeln ebelp
      INTO TABLE gt_eban
      FROM eban FOR ALL ENTRIES IN gt_eket
      WHERE
      banfn = gt_eket-banfn
     and banfpo = gt_eket-banfpo.
if sy-subrc = 0.
delete gt_eban where ernam not in s_ernam.
endif.
endif.
endif.
endif.
2nd Suggestion:
if gt_ekko_ekpo[] is not initial.
SELECT banfn banfpo       INTO TABLE gt_eket
      FROM eket FOR ALL ENTRIES IN gt_ekko_ekpo
      WHERE
     ebeln = gt_ekko_ekpo-ebeln AND
      ebelp = gt_ekko_ekpo-ebelp.
if sy-subrc = 0.
delete gt_eket where banfn not in s_banfn.
if gt_eket[] is not initial
SELECT banfn bnfpo ernam badat ebeln ebelp
      INTO TABLE gt_eban
      FROM eban FOR ALL ENTRIES IN gt_eket
      WHERE
      banfn = gt_eket-banfn
     and banfpo = gt_eket-banfpo
     and ernam in s_ernam.
endif.
endif.
endif.
Hope this helps.
Regards,
R

How to know query execution time in sql plus

HI
I want to know the query execution time in sql plus along with statistics
I say set time on ;
set autotrace on ;
select * from view where usr_id='abcd';
if the result is 300 rows it scrolls till all the rows are retrieved and finally gives me execution time as 40 seconds or 1 minute.. (this is after all the records are scrolled )
but when i execute it in toad it gives 350 milli seconds..
i want to see the execution time in sql how to do this
database server 11g and client is 10g
regards
raj

what is the difference between .. the
statistics gathered in sql plus something like this and the one that i get from plan_table in toad?
how to format the execution plan I got in sqlplus in a proper understanding way?
statistics in sqlplus
tatistics
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         0 db block gets
       164 consistent gets
         0 physical reads
         0 redo size
     29805 bytes sent via SQL*Net to client
       838 bytes received via SQL*Net from client
        25 SQL*Net roundtrips to/from client
         1 sorts (memory)
         0 sorts (disk)
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xecution Plan
0      SELECT STATEMENT Optimizer=ALL_ROWS (Cost=21 Card=1 Bytes=10
         03)
1    0   HASH (UNIQUE) (Cost=21 Card=1 Bytes=1003)
2    1     MERGE JOIN (CARTESIAN) (Cost=20 Card=1 Bytes=1003)
3    2       NESTED LOOPS
4    3         NESTED LOOPS (Cost=18 Card=1 Bytes=976)
5    4           NESTED LOOPS (Cost=17 Card=1 Bytes=797)
6    5             NESTED LOOPS (OUTER) (Cost=16 Card=1 Bytes=685)
7    6               NESTED LOOPS (OUTER) (Cost=15 Card=1 Bytes=556
8    7                 NESTED LOOPS (Cost=14 Card=1 Bytes=427)
9    8                   NESTED LOOPS (Cost=5 Card=1 Bytes=284)
10    9                     TABLE ACCESS (BY INDEX ROWID) OF 'USR_XR
         EF' (TABLE) (Cost=4 Card=1 Bytes=67)
11   10                       INDEX (RANGE SCAN) OF 'USR_XREF_PK' (I
         NDEX (UNIQUE)) (Cost=2 Card=1)
12    9                     TABLE ACCESS (BY INDEX ROWID) OF 'USR_DI
         M' (TABLE) (Cost=1 Card=1 Bytes=217)
13   12                       INDEX (UNIQUE SCAN) OF 'USR_DIM_PK' (I
         NDEX (UNIQUE)) (Cost=0 Card=1)
14    8                   TABLE ACCESS (BY INDEX ROWID) OF 'HDS_FCT'
          (TABLE) (Cost=9 Card=1 Bytes=143)
15   14                     INDEX (RANGE SCAN) OF 'HDS_FCT_IX2' (IND
         EX) (Cost=1 Card=338)
16    7                 TABLE ACCESS (BY INDEX ROWID) OF 'USR_MEDIA_
         COMM' (TABLE) (Cost=1 Card=1 Bytes=129)
17   16                   INDEX (UNIQUE SCAN) OF 'USR_MEDIA_COMM_PK'
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18    6               TABLE ACCESS (BY INDEX ROWID) OF 'USR_MEDIA_CO
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19   18                 INDEX (UNIQUE SCAN) OF 'USR_MEDIA_COMM_PK' (
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20    5             TABLE ACCESS (BY INDEX ROWID) OF 'PROD_DIM' (TAB
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21   20               INDEX (UNIQUE SCAN) OF 'PROD_DIM_PK' (INDEX (U
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22    4           INDEX (UNIQUE SCAN) OF 'CUST_DIM_PK' (INDEX (UNIQU
         E)) (Cost=0 Card=1)
23    3         TABLE ACCESS (BY INDEX ROWID) OF 'CUST_DIM' (TABLE)
         (Cost=1 Card=1 Bytes=179)
24    2       BUFFER (SORT) (Cost=19 Card=22 Bytes=594)
25   24         INDEX (FAST FULL SCAN) OF 'PROD_DIM_AK1' (INDEX (UNI
         QUE)) (Cost=2 Card=22 Bytes=594)

Why does it take iTunes along time to imports CD'S ?

Hi
I was wondering why does it take iTunes along time to import CD's I am using iTunes version 7.02 . Does anyone else have this problem and how do I fix it?
I would appreciate any help,
lizabler
Fifth Generation iPod Windows XP

Hey lizabler!
Here's a sugestion someone found to be a "workaround" for this issue with iTunes 7:
Don't leave iTunes showing the CD screen, which shows the track names and the importing progress. Click on the library, or iTunes store, as not to leave iTunes on the CD importing screen.
After doing this, your importing speed might increase to a good level once more.
I hope that helps you.
-Kylene

Same query on different RAC instance huge execution time difference

we have 3 nodes oracle 10gR2 RAC based on ASM. The 3rd node is the latest one we added into the cluster. All instances on 3 nodes using the same system parameters and same OS and same hardware
i found a weird problem, a same query i executed on node1 is way more faster than on node3 (1.5mins VS. 18mins). Then i did trace, surprising found the fetch time for node3 is longer than node1. Both nodes are at very low load. here is part of tracing for both nodes:
node1:
call count cpu elapsed disk query current rows
Parse 1 3.40 3.47 0 0 0 0
Execute 1 0.00 0.00 0 0 0 0
Fetch 2 19.13 97.04 69938 269374 0 7
total 4 22.54 100.51 69938 269374 0 7
Misses in library cache during parse: 1
Optimizer mode: ALL_ROWS
Parsing user id: 5
Elapsed times include waiting on following events:
Event waited on Times Max. Wait Total Waited
---------------------------------------- Waited ---------- ------------
row cache lock 132 0.00 0.03
library cache lock 13 0.00 0.00
library cache pin 9 0.00 0.00
rdbms ipc reply 6 0.00 0.00
latch: shared pool 1 0.00 0.00
SQL*Net message to client 2 0.00 0.00
gc current block 2-way 2061 0.00 0.67
gc cr multi block request 76610 0.18 7.71
gc current block 3-way 801 0.00 0.33
gc cr block 3-way 3 0.00 0.00
gc cr block 2-way 30 0.00 0.01
db file scattered read 1167 0.02 3.66
gc cr grant 2-way 24739 0.00 4.81
db file sequential read 37363 0.12 57.35
latch: KCL gc element parent latch 7 0.00 0.00
db file parallel read 1465 0.05 5.86
latch: cache buffers lru chain 1 0.00 0.00
gc current grant 2-way 1 0.00 0.00
gc cr block busy 10 0.17 0.37
gc cr disk read 1 0.00 0.00
SQL*Net more data to client 5 0.00 0.00
SQL*Net message from client 2 436.40 436.40
node3
call count cpu elapsed disk query current rows
Parse 1 2.58 2.64 0 0 0 0
Execute 1 0.00 0.00 0 0 0 0
Fetch 2 11.35 299.22 37084 269364 0 7
total 4 13.94 301.86 37084 269364 0 7
Misses in library cache during parse: 1
Optimizer mode: ALL_ROWS
Parsing user id: 5
Elapsed times include waiting on following events:
Event waited on Times Max. Wait Total Waited
---------------------------------------- Waited ---------- ------------
library cache lock 3 0.00 0.00
row cache lock 10 0.00 0.00
SQL*Net message to client 2 0.00 0.00
gc cr grant 2-way 23126 0.01 5.01
db file sequential read 37080 1.30 277.16
gc cr multi block request 1 0.00 0.00
db file scattered read 1 0.31 0.31
read by other session 721 0.03 2.12
gc buffer busy 1248 0.03 4.78
latch: cache buffers chains 5 0.00 0.00
gc current block 3-way 332 0.00 0.17
gc current block 2-way 834 0.00 0.30
latch: KCL gc element parent latch 1 0.00 0.00
gc current grant 2-way 1 0.00 0.00
SQL*Net more data to client 5 0.00 0.00
SQL*Net message from client 2 76.12 76.12
And all the execution plan are the same.
Could anybody please tell me why this happens?
Thanks!

To me, it looks like node3 is not accessing storage as fast as node 1 is. Look at this:
db file sequential read 37363 0.12 57.35
db file sequential read 37080 1.30 277.16
both cases have roughly the same amount of reads/waits but the time waited is 5 times more in the second case. So this could indicate a problem, maybe something with the HBA or SAN path or something like that.
Bjoern

Why same query takes different execution time in sql 2008

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