## 8.2\. File I/O Access Performance

Providing a common baseline for a consistent file access performance on the
application private data storage (`/data` partition) allows app developers
to set a proper expectation that would help their software design. Device
implementations, depending on the device type, MAY have certain requirements
described in [section 2](#2_device-type) for the following read
and write operations:

*    **Sequential write performance**. Measured by writing a 256MB file using
10MB write buffer.
*    **Random write performance**. Measured by writing a 256MB file using 4KB
write buffer.
*    **Sequential read performance**. Measured by reading a 256MB file using
10MB write buffer.
*    **Random read performance**. Measured by reading a 256MB file using 4KB
write buffer.