Oracle RAC SQL Workload Test

Nothing can degrade the performance of an Oracle cluster like a resource-hungry or a long-running query! When such queries execute on the cluster, they either hog almost all the available CPU, memory, and disk resources of the cluster or keep the resources locked for long time periods, thus leaving little to no resources for carrying out other critical cluster operations. This can significantly slowdown the cluster and adversely impact user experience with the cluster. To ensure peak performance of the Oracle cluster at all times, such queries should be rapidly identified and quickly optimized to minimize resource usage. This is where the Oracle SQL Workload test helps.

At configured intervals, this test compares the usage levels and execution times of all queries that started running on the cluster in the last measurement period and identifies a ‘top query’ in each of the following categories - CPU usage, memory usage, disk activity, and execution time. The test then reports the resource usage and execution time of the top queries and promptly alerts administrators if any query consumes more resources or takes more time to execute than it should. In such a scenario, administrators can use the detailed diagnosis of this test to view the inefficient queries and proceed to optimize them to enhance cluster performance.

Target of the test : Oracle Cluster

Agent deploying the test : An internal agent

Outputs of the test : One set of results for each node in the Oracle cluster being monitored

Configurable parameters for the test
TEST PERIOD - How often should the test be executed Host – The host for which the test is to be configured Port - The port on which the server is listening orasid - The variable name of the oracle instance service name - 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, the service name is set to none. In this case, the test connects to the cluster using the orasid and pulls out the metrics from that database instance which corresponds to that orasid. If a valid service name is 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’ User – 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 – Password of the specified database user Confirm password – Confirm the password by retyping it here. 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. TRUSSTORE 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. ddcount – By default, the detailed diagnosis of this test reports the top-5 queries in resource usage and execution time. This is why, the ddcount parameter is set to 5 by default. If you want detailed diagnosis to display less or more number of top queries, then change the ddcount. 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
Top most query physical reads:	Indicates the number of physical disk reads performed by the top query per execution.	Reads/execution	If the value of this measure is abnormally high, you can use the detailed diagnosis of this measure to view the top-5 (by default) queries generating maximum physical disk activity. From this, you can identify the top query in terms of number of physical disk reads. You may then want to optimize the query to reduce the disk reads.
Top most buffer gets:	Indicates the number of memory buffers used by the top query per execution.	Memorybuffergets/execution	If the value of this measure is abnormally high, you can use the detailed diagnosis of this measure to view the top-5 (by default) queries consuming memory excessively. From this, you can easily pick that query which is consuming the maximum memory. You may then want to optimize the query to minimize memory usage.
Top most query CPU time:	Indicates the duration for which each execution of the top query was hogging the CPU resources.	Secs/execution	If the value of this measure is over 30 seconds, you can use the detailed diagnosis of this measure to the top-5 (by default) queries hogging the CPU resources. From this, you can easily pick that query which is consuming the maximum CPU. You may then want to optimize the query to minimize CPU usage.
Top most query elapsed time:	Indicates the running time of each execution of the top query.	Secs/execution	If the value of this measure crosses 10 seconds, you can use the detailed diagnosis of this measure to view the top-5 (by default) queries that are taking too long to execute. . From this, you can easily pick that query with the maximum execution time. You may then want to optimize the query to minimize execution time.