This option disables the use of page cache (file content cache)
in the kernel for this filesystem. This has several affects:
1. Each read(2) or write(2) system call will initiate one
or more read or write operations, data will not be
cached in the kernel.
2. The return value of the read() and write() system calls
will correspond to the return values of the read and
write operations. This is useful for example if the
file size is not known in advance (before reading it).
Internally, enabling this option causes fuse to set the
direct_io field of struct fuse_file_info - overwriting
any value that was put there by the file system.
This option disables the use of page cache (file content cache) in the kernel for this filesystem. This has several affects:
1. Each read(2) or write(2) system call will initiate one or more read or write operations, data will not be cached in the kernel.
2. The return value of the read() and write() system calls will correspond to the return values of the read and write operations. This is useful for example if the file size is not known in advance (before reading it).
Internally, enabling this option causes fuse to set the direct_io field of struct fuse_file_info - overwriting any value that was put there by the file system.