Required Help to analyze High IO Wait caused Node Eviction — oracle-tech

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Required Help to analyze High IO Wait caused Node Eviction

User_7I5HEUser_7I5HE Posts: 4 Red Ribbon

We have three node cluster and highly capable DB server with High IO capacity

I have taken two ASH report:

1st report --> Normal Office Hours , not much background use: 14:00 to 15:00

Top 10 Foreground Events by Total Wait Time

EventWaitsTotal Wait Time (sec)Wait Avg(ms)% DB timeWait Class
DB CPU 35.6K 65.1
db file sequential read11,009,9707064.8112.9User I/O
gc buffer busy acquire4,828,8724404.518.1Cluster
gc cr grant 2-way7,148,7651436.802.6Cluster
enq: TX - row lock contention1,160136211742.5Application
gc current block 2-way6,048,7571294.902.4Cluster
gc cr block busy517,6741071.522.0Cluster
gc current block 3-way1,804,308685.101.3Cluster
direct path read445,452613.211.1User I/O
SQL*Net message from dblink308,012562.821.0Network

Wait Classes by Total Wait Time

Wait ClassWaitsTotal Wait Time (sec)Avg Wait (ms)% DB timeAvg Active Sessions
DB CPU 35,576 65.19.9
Cluster21,844,5699,716017.82.7
User I/O13,500,0048,424115.42.3
Application11,8351,3741162.50.4
Network3,065,9641,02801.90.3
Other5,395,88576101.40.2
System I/O475,4432661.50.1
Commit95,5062092.40.1
Concurrency1,930,398840.20.0
Configuration53901.00.0

2nd Report --> Last One hour before Node reboot happened due to high IO.

op 10 Foreground Events by Total Wait Time

EventWaitsTotal Wait Time (sec)Wait Avg(ms)% DB timeWait Class
DB CPU 28.6K 56.0
gc buffer busy acquire11,547,5007336.7114.3Cluster
db file sequential read9,030,6526024.2111.8User I/O
enq: TX - row lock contention234266.71855098.3Application
gc cr block busy720,6681267.522.5Cluster
gc current block 2-way4,887,498864.501.7Cluster
gc cr grant 2-way5,816,336841.501.6Cluster
read by other session1,348,391592.501.2User I/O
gc cr multi block request866,343462.71.9Cluster
gc current grant 2-way2,560,953357.30.7Cluster

Wait Classes by Total Wait Time

Wait ClassWaitsTotal Wait Time (sec)Avg Wait (ms)% DB timeAvg Active Sessions
DB CPU 28,624 56.09.5
Cluster28,713,33211,785023.03.9
User I/O13,431,0878,009115.72.7
Application7,4994,2695698.31.4
Other8,719,97470801.40.2
Network1,729,73759401.20.2
System I/O752,6713230.60.1
Commit41,176912.20.0
Concurrency3,238,306660.10.0
Configuration23013.00.0

How I can debug this further ?

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