Oracle RAC Table Locks Test

In Oracle RAC (Real Application Clusters), a table lock is a mechanism used to control concurrent access to a table across multiple instances in the cluster. It ensures data consistency and integrity when multiple users or sessions attempt to access or modify the same table. A table lock prevents conflicting operations on a table. Monitoring table locks in Oracle RAC is crucial for maintaining database performance, availability, and consistency across the cluster.

This test continuously monitors the table locks in Oracle RAC , and reports the metrics like - Table locks acquired, Waiting for table locks, Maximum waiting duration for table locks and Maximum duration of table locks.

Note:

This test is applicable only for PDB (Pluggable Database) configuration of Oracle Clusters with Multi-tenant support.

Target of the test : An Oracle Cluster

Agent deploying the test : An internal agent

Outputs of the test : One set of results for each instance on the Oracle Cluster that is being monitored

Configurable parameters for the test
Parameters	Description
Test period	How often should the test be executed. By default, this is set to 60 minutes.
Host	The IP address of the Oracle server.
Port	The port number through which the Oracle server communicates. The default port is 1521.
SCAN Name	SCAN stands for Single Client Access Name, it is a feature used in Oracle RAC environments that provide a single name for clients to access any Oracle Database running in the cluster. You can provide SCAN as an alternative to IP/Host Name. If this parameter value is provided, it will be used for connectivity otherwise IP/Hostname will be used.
Connecting Port	Specify the port number at which eG Enterprise will connect to Oracle Cluster.
OraSID	The variable name of the oracle instance.
ServiceName	A ServiceName exists for the entire Oracle RAC system. When clients connect to an Oracle cluster using the ServiceName, then the cluster routes the request to any available database instance in the cluster. By default, this is set to none. In this case, the test connects to the cluster using the OraaSID and pulls out the metrics from that database instance which corresponds to that OraSID. If a valid service nameis specified instead, then, the test will connect to the cluster using that service name, and will be able to pull out metrics from any available database instance in the cluster. To know the ServiceName of a cluster, execute the following query on any node in the target cluster: select name, value from v$parameter where name =’service_names’
Username	In order to monitor an Oracle RAC, a special database user account has to be User – In order to monitor an Oracle database server, a special database user account has to be created in every Oracle database instance that requires monitoring. A Click here hyperlink is available in the test configuration page, using which a new oracle database user can be created. Alternatively, you can manually create the special database user. When doing so, ensure that this user is vested with the select_catalog_role and create session privileges. The sample script we recommend for user creation (in Oracle database server versions before 12c) for eG monitoring is: create user oraeg identified by oraeg create role oratest; grant create session to oratest; grant select_catalog_role to oratest; grant oratest to oraeg; The sample script we recommend for user creation (in Oracle database server 12c) for eG monitoring is: alter session set container=<Oracle_service_name>; create user <user_name>identified by <user_password> container=current default tablespace <name_of_default_tablespace> temporary tablespace <name_of_temporary_tablespace>; Grant create session to <user_name>; Grant select_catalog_role to <user_name>; The name of this user has to be specified here.
Password	Specify the password corresponding to the mentioned user.
Confirm Password	Confirm the password by retyping it.
Lock Duration Seconds	Specify the duration after which the lock will be released. By default, this is set to 10 Seconds.
SSL	By default, this flag is set to No, as the target Oracle cluster is not SSL-enabled by default. If the target cluster is SSL-enabled, then set this flag to Yes.
SSL Cipher	This parameter is applicable only if the target Oracle Cluster is SSL-enabled, if not, set this parameter to none. A cipher suite is a set of cryptographic algorithms that are used before a client application and server exchange information over an SSL/TLS connection. It consist of sets of instructions on how to secure a network through SSL (Secure Sockets Layer) or TLS (Transport Layer Security). In this text box, provide a comma-seperated list of cipher suites that are allowed for SSL/TLS connection to the target cluster. By default, this parameter is set to none.
Truststore File	This parameter is applicable only if the target Oracle Cluster is SSL-enabled, if not, set this parameter to none. TrustStore is used to store certificates from Certified Authorities (CA) that verify and authenticate the certificate presented by the server in an SSL connection. Therefore, the eG agent should have access to the truststore where the certificates are stored to authenticate and connect with the target cluster and collect metrics. For this, first import the certificates into the following default location <eG_INSTALL_DIR>/lib/security/mytruststore.jks. To know how to import the certificate into the truststore, refer toPre-requisites for monitoring Oracle Cluster. Then, provide the truststore file name in this text box. For example: mytruststore.jks. By default, none is specified against this text box.
Truststore Type	This parameter is applicable only if the target Oracle Cluster is SSL-enabled, if not, set this parameter to none.Specify the type of truststore that contains the certificates for server authentication in this text box. For eg.,JKS. By default, this parameter is set to the value none.
Truststore Password	This parameter is applicable only if the target Oracle Cluster is SSL-enabled, if not, set this parameter to none. If a Truststore File name is provided, then, in this text box, provide the password that is used to obtain the associated certificate details from the Truststore File. By default, this parameter is set to none.
Keystore File	This parameter is applicable only if the target Oracle Cluster is SSL-enabled, if not, set this parameter to none. Keystore contains the private keys for the certificates that the client can provide to the server upon request. eG agent requires access to the keystore where client certificate is stored to send that to the server so that the server validates the certificate against the one contained in its trustore. For this purpose, first create the client certificate in the following default location EG_INSTALL_DIR/jre/lib/security/mykeystore.jks. Then, provide the keystore file name in this text box. For example: mykeystore.jks. By default, none is specified against this text box.
Keystore Password	This parameter is applicable only if the target Oracle Cluster is SSL-enabled, if not, set this parameter to none. If a Keystore File name or file path is provided, then, in this text box, provide the password that is used to obtain the associated certificate details from the Keystore File.
Confirm Password	Confirm the Password for Keystore by retyping it here.
DD Frequency	Refers to the frequency with which detailed diagnosis measures are to be generated for this test. The default is 1:1. This indicates that, by default, detailed measures will be generated every time this test runs, and also every time the test detects a problem. You can modify this frequency, if you so desire. Also, if you intend to disable the detailed diagnosis capability for this test, you can do so by specifying none against DD frequency.
Detailed Diagnosis	To make diagnosis more efficient and accurate, the eG Enterprise embeds an optional detailed diagnostic capability. With this capability, the eG agents can be configured to run detailed, more elaborate tests as and when specific problems are detected. To enable the detailed diagnosis capability of this test for a particular server, choose the On option. To disable the capability, click on the Off option. The option to selectively enable/disable the detailed diagnosis capability will be available only if the following conditions are fulfilled: The eG manager license should allow the detailed diagnosis capability Both the normal and abnormal frequencies configured for the detailed diagnosis measures should not be 0.

Measurements made by the test
Measurement	Description	Measurement Unit	Interpretation
Table locks acquired	Indicates the number of Table locks acquired during the last measurement period.	Number	Table locks are acquired to manage concurrent access to tables across multiple database instances. These locks ensure data consistency, transaction integrity, and conflict avoidance when multiple sessions attempt to access or modify the same table.
Maximum duration of table locks	Indicates the maximum duration of table locks.	Seconds
Waiting for table locks	Indicates the number of operations waiting for table locks.	Number	A table lock enters a waiting state when a session requests a lock on a table that is already locked by another session, and the requested lock conflicts with the existing one. This waiting state is part of Oracle's concurrency control mechanism to ensure data integrity and consistency across multiple RAC nodes.
Maximum waiting duration for table locks	Indicates the maximum waiting duration for table locks.	Seconds