Using Large Files With XFS

Using Large Files With XFS

An application may create or encounter files greater than 2 gigabytes with XFS. If a program is doing sequential I/O and does not maintain internal byte counters, files greater than 2 Gb won't encounter problems.

However, if an application uses internal byte counters, then modifications are required.

Table 7-3 lists potential problems and modifications required to enable files greater than 2 Gb to run on XFS.

Modifications for Applications on XFS
Application Modification
Uses an internal byte counter while reading Change to type long long
Uses certain system calls such as lseek() and stat() that use 32-bit off_t Use lseek64(), stat64(), and so forth
Relies on internal features of EFS (such as reads the raw disk) Rewrite the application (so it doesn't read the raw disk)

Modifications for Applications on XFS
Application	Modification
Uses an internal byte counter while reading	Change to type long long
Uses certain system calls such as lseek() and stat() that use 32-bit off_t	Use lseek64(), stat64(), and so forth
Relies on internal features of EFS (such as reads the raw disk)	Rewrite the application (so it doesn't read the raw disk)

For more information about XFS, see Getting Started With XFS Filesystems.