DB running slow...
I have a Oracle 11.2.0.3 system that is running on RHEL with 12 CPU and 6 Cores on 48GB of ram.
We are in the process of upgrading our ERP system and are testing some workload of the system during upgrade process. I've noticed that there is a lot of waits on free buffer waits and log file sync.
Top 5 Timed Foreground Events
Event Waits Time(s) Avg wait (ms) % DB time Wait Class
free buffer waits 62,162 7,110 114 47.98 Configuration
log file sync 210,635 2,935 14 19.81 Commit
db file scattered read 1,078,317 1,308 1 8.83 User I/O
DB CPU 890 6.01
db file sequential read 83,378 739 9 4.99 User I/O
The database is running on no archive log for now. The buffer cache is at 7904M and shared Pool size is 1280M. Log Buffer is at 21,200K. Automatic Memory management is enabled. I also ran IOSTAT and looks the hard drive is getting worked really hard but seems like CPU is fairly idle?
avg-cpu: %user %nice %system %iowait %steal %idle
1.53 0.00 0.75 4.82 0.00 92.90
Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn
sda 1.00 0.00 83.20 0 416
sda1 0.00 0.00 0.00 0 0
sda2 1.00 0.00 83.20 0 416
sdb 0.60 0.00 56.00 0 280
sdc 0.00 0.00 0.00 0 0
sdd 0.00 0.00 0.00 0 0
sde 0.00 0.00 0.00 0 0
sdf 166.20 268.80 1331.20 1344 6656
sdg 273.40 440.00 2185.60 2200 10928
sdh 0.00 0.00 0.00 0 0
sdi 0.00 0.00 0.00 0 0
sdj 0.00 0.00 0.00 0 0
sdk 1.40 0.00 115.20 0 576
sdl 0.40 0.00 4.80 0 24
sdm 0.00 0.00 0.00 0 0
sdn 280.80 451.20 2252.80 2256 11264
sdo 173.40 280.00 1387.20 1400 6936
sdp 0.00 0.00 0.00 0 0
sdq 9.00 907.20 177.60 4536 888
dm-0 10.40 0.00 83.20 0 416
dm-1 0.00 0.00 0.00 0 0
dm-2 7.00 0.00 56.00 0 280
dm-3 14.40 0.00 115.20 0 576
dm-4 0.60 0.00 4.80 0 24
dm-5 0.00 0.00 0.00 0 0
dm-6 538.00 720.00 3584.00 3600 17920
dm-7 536.20 720.00 3569.60 3600 17848
dm-8 0.00 0.00 0.00 0 0
dm-9 33.60 907.20 177.60 4536 888
anyone have any ideas why I'm the database is experiencing such slow speed?
thanks!