oracledb {usl}

Performance of an Oracle database used for online transaction processing

Description

A dataset containing performance data for an Oracle OLTP database measured between 8:00am and 8:00pm on January, 19th 2012. The measurements were recorded for two minute intervals during this time and a timestamp indicates the end of the measurement interval. The performance metrics were taken from the v$sysmetric family of system performance views.

Format

A data frame with 360 rows on 8 variables

Details

The Oracle database was running on a 4-way server.

The data frame contains different types of measurements:

• Variables of the "time" type are expressed in seconds per second.

• Variables of the "rate" type are expressed in events per second.

• Variables of the "util" type are expressed as a percentage.

The data frame contains the following variables:

• timestamp The end of the two minute interval for which the remaining variables contain the measurements.

• db_time The time spent inside the database either working on a CPU or waiting (I/O, locks, buffer waits ...). This time is expressed as seconds per second, so two sessions working for exactly one second each will contribute a total of two seconds per second of db_time. In Oracle this value is also known as Average Active Sessions (AAS).

• cpu_time The CPU time used during the interval. This is also expressed as seconds per second. A 4-way machine has a theoretical capacity of four CPU seconds per second.

• call_rate The number of user calls (logins, parses, or execute calls) per second.

• exec_rate The number of statement executions per second.

• lio_rate The number of logical I/Os per second. A logical I/O is the Oracle term for a cache hit in the database buffer cache. This metric does not indicate if an additional physical I/O was necessary to load the buffer from disk.

• txn_rate The number of database transactions per second.

• cpu_util The CPU utilization of the database server in percent. This was also measured from within the database.