FILESYNC= System Option

Specifies when operating system buffers that contain contents of permanent SAS files are written to disk.

Valid in:	Configuration file, SAS invocation
Category:	Files: SAS Files
PROC OPTIONS GROUP=	SASFILES
Note:	This option can be restricted by a site administrator. For more information, see Restricted Options.
See:	FILESYNC= System Option: z/OS in SAS Companion for z/OS

Syntax

Details

Syntax

FILESYNC= SAS | CLOSE | HOST | SAVE

Syntax Description

SAS: specifies that SAS requests the operating system to force buffered data to be written to disk when it is best for the integrity of the SAS file.

CLOSE: specifies that SAS requests the operating system to force buffered data to be written to disk when the SAS file is closed.

HOST: specifies that the operating system schedules when the buffered data for a SAS file is written to disk. This is the default.

SAVE: specifies that the buffers are written to disk when the SAS file is saved.

Details

By using the FILESYNC= system option, SAS can tell the operating system when to force data that is temporarily stored in operating system buffers to be written to disk. Only SAS files in a permanent SAS library are affected; files in a temporary library are not affected.

If you specify a value other than the default value of HOST, the following occurs:

the length of time it takes to run a SAS job increases
the small chance of loosing data in the event of a system failure is further reduced

Consult with your system administrator before you change the value of the FILESYNC= system option to a value other than the default value.

z/OS Specifics: Under z/OS, the FILESYNC= system option affects SAS files only in UNIX file system (UFS) libraries. For more information, see FILESYNC= System Option: z/OS in SAS Companion for z/OS.