Methodology - Expert Oracle RAC Performance Diagnostics and Tuning - page 8

Similarly, if the problem statement is around the instance or node crashing frequently in a RAC environment, the
information that has to be gathered is centered on the RAC cluster:

• Collecting data from the

/var/log/messages from the system administrators
Adding additional debug flags to the cluster services to gather additional information in the

•

various GRID (Cluster Ready Services [CRS]) infrastructure log files and so forth

In Oracle Database 11g Release 2, and recently in Oracle Database 12c Release 1, there are several additional
components added to the clusterware, which means several more log files (illustrated in Figure 1-1 ) to look into when
trying to identify reasons for problems.

acfs

ohasd

orarootagent_root
oragent_oracle

crsd
cssd

oracssdmonitor_root
oracssdagent_root

evmd
agent

diag

gpnpd
gnsd

orarootagent_root
oragent_oracle

<nodename>
e.g.. ssky1l1p1

client
gipcd
diskmon

GRID HOME log

scriptagent_oracle

srvm

crs

admin

ctssd
mdnsd racgmain

racg racgevtf

racgeut cvu

crflogd
crfmond

alert<nodename>.log

Figure 1-1. Oracle 11g R2 grid component log files

Area Identification
Once the information concerning the performance issue is gathered, the next step is to identify the area of the
application system that is reported to have a performance issue. Most of the time, the information gathered during
the previous step of the methodology is sufficient. However, this may require a fine-grained look at the data and
statistics collected.