!--a11y-->You can use this procedure to display the file system requests.
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1. Choose Tools ® Administration ® Computing Center ® Management System ® Control ® Performance Menu ® Database ® Activity.
Alternatively, use transaction code ST04.
2. Choose Detail analysis menu ® Filesystem requests.
This screen displays statistics on physical accesses to database files. The display includes duration for block reads and writes measured in milliseconds. To display these time values, you must set the init<SID>.ora parameter timed_statistics (TIMED_STATISTICS (Oracle)) to true.
3. To minimize the time needed for reading from or writing to a data file:
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a. Identify the frequently used data files
b. Ensure that frequently used files are on separate disks so that I/O requests for objects do not directly compete with each other.

Data file activity has an important effect on performance if your database is very large and is used intensively.