Re: Performance problems after moving to new hardware

From: Iliya Peregoudov <iperegudov_at_cboss.ru>
Date: Thu, 05 Mar 2015 11:30:06 +0300
Message-ID: <54F8140E.5060000_at_cboss.ru>

I think I correctly decrypted AWR stats.

AWR from old server

Host CPU (CPUs: 32 Cores: 16 Sockets: 4)

Event                      Waits  Time(s)  Avg wait (ms)  % DB time 

Wait Class

-----------------------  -------  -------  -------------  --------- 
----------
db file parallel read     72,570    4,355             60      50.98 
User I/O
DB CPU                     2,092                              24.49
db file sequential read  387,105    1,308              3      15.31 
User I/O
direct path write temp     3,227      509            158       5.96 
User I/O
db file scattered read   133,051      236              2       2.27 

User I/O

Snap Time Load %busy %user %sys %idle %iowait

---------------  -----  -----  -----  -----  -----  -------
24-Feb 10:00:42   1.06
24-Feb 11:00:59   2.02   4.40   1.74   2.66  95.60     0.00

AWR from new server

Host CPU (CPUs: 32 Cores: 4 Sockets: 1)

Event                      Waits  Time(s)  Avg wait (ms)  % DB time 

Wait Class

-----------------------  -------  -------  -------------  --------- 
----------
db file parallel read     46,337   18,808            406      43.47 
User I/O
db file sequential read  154,062    6,861             45      15.86 
User I/O
direct path write temp     8,394    3,203            382       7.40 
User I/O
log file sync              3,002    1,564            521       3.61  Commit
DB CPU                     1,433                               3.31

Snap Time         Load  %busy  %user   %sys  %idle  %iowait
---------------  -----  -----  -----  -----  -----  -------
03-Mar 10:00:42   2.73
03-Mar 11:00:37   2.95   7.12   4.69   2.43  92.88     0.00

New server waits for I/O much more per hour (30k seconds vs 6k seconds). Average read waits are also 10 times larger on new server (406ms vs 60ms, 45ms vs 3ms). CPU on new server is under-loaded I think because of waits. It seems that old server was better balanced in IO/CPU throughput.

On 04.03.2015 18:48, Ls Cheng wrote:
> I cant read anything useful, cant you format the output or paste a
> screenshot :-?

--
http://www.freelists.org/webpage/oracle-l

Received on Thu Mar 05 2015 - 09:30:06 CET