Home » RDBMS Server » Performance Tuning » Help required in analyzing Network waits from AWR (Oracle 10.2.0.3 on AIX)
| Help required in analyzing Network waits from AWR [message #585763] |
Wed, 29 May 2013 10:19  |
 |
sysdba007
Messages: 28
Registered: November 2012
|
Junior Member |
|
|
Hello
We are experiencing Network waits on one of our 2-node clustered databases
In every 1 hour of clock time we are finding 700-900 seconds of Network waits
From the AWR data I find that "ARCH wait on SENDREQ" is one of the main constituent for these Network waits and as such I suspect Network between Production database and its corresponding database might be slow
Question 1) Does this understanding look correct?
Question 2) Apart from the above what could be the other causes of the Network waits. Can we point out any particular area from following AWR extract
Seeing some gc* waits initially I thought it might be due to slow interconnect between the cluster nodes but some google search denotes it is not the case
So what could be other causes? I mean which network link I would check?
Thanks and Regards
sysdba007
Snap Id Snap Time Sessions Curs/Sess
--------- ------------------- -------- ---------
Begin Snap: 22631 22-May-13 10:00:11 976 7.9
End Snap: 22632 22-May-13 11:00:28 978 8.1
Elapsed: 60.29 (mins)
DB Time: 795.66 (mins)
Cache Sizes
~~~~~~~~~~~ Begin End
---------- ----------
Buffer Cache: 41,856M 41,856M Std Block Size: 8K
Shared Pool Size: 4,768M 4,768M Log Buffer: 14,268K
Load Profile
~~~~~~~~~~~~ Per Second Per Transaction
--------------- ---------------
Redo size: 881,316.98 8,680.32
Logical reads: 196,666.10 1,937.01
Block changes: 4,272.03 42.08
Physical reads: 2,284.29 22.50
Physical writes: 265.63 2.62
User calls: 8,806.28 86.74
Parses: 3,668.13 36.13
Hard parses: 0.79 0.01
Sorts: 408.40 4.02
Logons: 0.10 0.00
Executes: 5,121.07 50.44
Transactions: 101.53
Avg
%Time Total Wait wait Waits
Wait Class Waits -outs Time (s) (ms) /txn
-------------------- ---------------- ------ ---------------- ------- ---------
User I/O 4,300,944 .0 30,916 7 11.7
Commit 375,147 .0 4,097 11 1.0
System I/O 447,588 .0 3,382 8 1.2
Cluster 914,194 .0 923 1 2.5
Network 35,607,365 .0 781 0 97.0
Application 47,874 2.6 775 16 0.1
Other 634,810 93.9 62 0 1.7
Configuration 1,068 .1 44 41 0.0
Concurrency 19,969 .3 22 1 0.1
-------------------------------------------------------------
%Time Total Wait wait Waits
Event Waits -outs Time (s) (ms) /txn
---------------------------- -------------- ------ ----------- ------- ---------
db file sequential read 3,856,417 .0 29,900 8 10.5
log file sync 375,147 .0 4,097 11 1.0
log file parallel write 293,891 .0 1,842 6 0.8
db file parallel write 114,875 .0 1,108 10 0.3
db file scattered read 394,943 .0 886 2 1.1
enq: TM - contention 2,839 42.5 665 234 0.0
gc cr grant 2-way 535,560 .0 443 1 1.5
ARCH wait on SENDREQ 3,342 .0 435 130 0.0
Log archive I/O 7,656 .0 312 41 0.0
SQL*Net more data from clien 1,820,698 .0 258 0 5.0
gc buffer busy 31,190 .1 218 7 0.1
gc current grant 2-way 185,697 .0 140 1 0.5
read by other session 15,751 .0 123 8 0.0
enq: TX - row lock contentio 979 1.8 98 101 0.0
Service Name DB Time (s) DB CPU (s) Reads Reads
-------------------------------- ------------ ------------ ---------- ----------
SYS$USERS 47,717.6 12,431.7 8,239,490 ##########
SYS$BACKGROUND 0.0 0.0 24,654 135,966
oradb 0.0 0.0 0 0
oradb.world 0.0 0.0 0 0
-------------------------------------------------------------
Service Wait Class Stats DB/Inst: oradb/oradb1 Snaps: 19631-19632
-> Wait Class info for services in the Service Statistics section.
-> Total Waits and Time Waited displayed for the following wait
classes: User I/O, Concurrency, Administrative, Network
-> Time Waited (Wt Time) in centisecond (100th of a second)
Service Name
----------------------------------------------------------------
User I/O User I/O Concurcy Concurcy Admin Admin Network Network
Total Wts Wt Time Total Wts Wt Time Total Wts Wt Time Total Wts Wt Time
--------- --------- --------- --------- --------- --------- --------- ---------
SYS$USERS
4265448 3090213 17415 1884 0 0 35603361 34662
SYS$BACKGROUND
35547 1400 2554 321 0 0 3342 43479
oradb.world
0 0 0 0 0 0 0 0
-------------------------------------------------------------
Statistic Name Time (s) % of DB Time
------------------------------------------ ------------------ ------------
sql execute elapsed time 41,939.8 87.9
DB CPU 12,436.2 26.1
parse time elapsed 504.7 1.1
PL/SQL execution elapsed time 133.2 .3
hard parse elapsed time 62.8 .1
connection management call elapsed time 2.6 .0
sequence load elapsed time 2.1 .0
repeated bind elapsed time 1.9 .0
PL/SQL compilation elapsed time 1.0 .0
hard parse (sharing criteria) elapsed time 0.5 .0
hard parse (bind mismatch) elapsed time 0.5 .0
DB time 47,739.4 N/A
background elapsed time 4,258.5 N/A
background cpu time 272.1 N/A
|
|
|
|
|
|
| Re: Help required in analyzing Network waits from AWR [message #585766 is a reply to message #585763] |
Wed, 29 May 2013 10:32  |
John Watson
Messages: 8960
Registered: January 2010
Location: Global Village
|
Senior Member |
|
|
I think you are trying to fix something that is does not need to be fixed. No end user has telephoned your help desk to complain that the "ARCH wait on SENDREQ" event is too high. It has no impact on response time or throughput and is therefore not a problem. And even if it were a problem, it is a tiny percentage of your 47739 seconds of DB Time.
If there is a performance problem, you should probably be looking at tuning the SQL to bring down the number of single block reads. It is those that are soaking up your DB Time.
|
|
|
|
|
|
Goto Forum:
Current Time: Sun Nov 24 09:18:33 CST 2024
|
] 
Blog
Search
Help
Members
Register
Login
Home
... Thanks to you Gurus from ORAFAQ forum, from whom I lerant many things