发表于: 2005.05.19 21:33
分类: Oracle is anything
出处: http://bitirainy.itpub.net/post/330/30396
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新系统IBM P590,AIX5.3,8 cpus /16G 内存,为了同时兼顾IO压力,我特地把 buffer cache 只给了1G大小。模拟应用的sql调用,用5台2 cpus的linux机器并发16*5 个线程同时循环跑一个client无IO的模拟应用的随机用户登陆流程(这个期间会运行一系列的sql)。linux机器上开16个线程同时跑的时候load 已经在2左右。而IBM服务器上cpu idle 2%,IO 为 read 40MB/S,write 8MB/S ,网络 IN 12MB/S , out 6MB/S。run queue (load)为 50。
在statspack采样数据load profile 为
STATSPACK report for
DB Name DB Id Instance Inst Num Release Cluster Host
------------ ----------- ------------ -------- ----------- ------- ------------
OCNDB 3701801852 ocndb 1 9.2.0.6.0 NO ocndb1
Snap Id Snap Time Sessions Curs/Sess Comment
--------- ------------------ -------- --------- -------------------
Begin Snap: 104 19-May-05 17:27:53 91 27.3
End Snap: 105 19-May-05 17:57:54 91 27.8
Elapsed: 30.02 (mins)
Cache Sizes (end)
~~~~~~~~~~~~~~~~~
Buffer Cache: 1,024M Std Block Size: 8K
Shared Pool Size: 512M Log Buffer: 2,048K
Load Profile
~~~~~~~~~~~~ Per Second Per Transaction
--------------- ---------------
Redo size: 344,880.30 555.47
Logical reads: 198,459.35 319.64
Block changes: 2,494.51 4.02
Physical reads: 5,105.48 8.22
Physical writes: 48.74 0.08
User calls: 84,336.12 135.83
Parses: 6,208.79 10.00
Hard parses: 0.03 0.00
Sorts: 1,242.01 2.00
Logons: 0.00 0.00
Executes: 19,867.03 32.00
Transactions: 620.88
% Blocks changed per Read: 1.26 Recursive Call %: 26.51
Rollback per transaction %: 0.00 Rows per Sort: 23.61
Instance Efficiency Percentages (Target 100%)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Buffer Nowait %: 99.30 Redo NoWait %: 100.00
Buffer Hit %: 97.43 In-memory Sort %: 100.00
Library Hit %: 100.02 Soft Parse %: 100.00
Execute to Parse %: 68.75 Latch Hit %: 99.32
Parse CPU to Parse Elapsd %: 34.12 % Non-Parse CPU: 96.74
Shared Pool Statistics Begin End
------ ------
Memory Usage %: 20.97 21.15
% SQL with executions>1: 83.85 83.54
% Memory for SQL w/exec>1: 88.18 85.88
Top 5 Timed Events
~~~~~~~~~~~~~~~~~~ % Total
Event Waits Time (s) Ela Time
-------------------------------------------- ------------ ----------- --------
CPU time 8,558 52.19
db file sequential read 9,194,762 4,730 28.84
buffer busy waits 2,500,799 1,639 10.00
log file sync 1,076,173 771 4.70
latch free 174,822 588 3.58
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看起来系统还是蛮强的,executions 为 19867次/S ,620个事务/S……











