Chapter Contents
Previous
Next
BLKSIZE(device-type)=

BLKSIZE(device-type)=


Specifies the default block size for SAS data libraries by device-type

Default: varies by device type, see table at end of section
Valid in: configuration file, SAS invocation, OPTIONS statement, OPTIONS window
Category: File Control: SASFILES
OS/390 specifics: all

Syntax
Details
See Also

Syntax

BLKSIZE(device-type)=value

device-type
specifies any valid specific device number, or DASD, DISK, or OTHER. DISK or DASD sets values for the device types 2301, 2303, 2305-1, 2305-2, 2314, 3330, 3330-1, 3340, 3350, 3375, 3380, 3390, and 9345.

OTHER
specifies a value that SAS uses when it is unable to determine the exact device type.

value
specifies the default block size. Valid values are

number
specifies the block size that SAS is to use for the device.

OPT
specifies that SAS is to choose an optimum block size for the device.

MAX or FULL
specifies that SAS is to use the maximum permitted block size for the device.

HALF, THIRD, FOURTH, or FIFTH
specifies that SAS is to use the largest value that results in obtaining two, three, four, and five blocks per track, respectively.

Details

The following example tells SAS to choose optimum block size values for all disk devices except 3380s, for which one-third track blocking is requested: 

options blksize(disk)=opt
        blksize(3380)=third;

BLKSIZE(device-type)= accepts values in the range of 1024-56664.

Default values and ranges of values are as follows:

Device Default Minimum Maximum
2301 6144 1024 20483
2303 4608 1024 4892
2305-1 6144 1024 14136
2305-2 6144 1024 14660
2314 6144 1024 7294
3330 6144 1024 13030
3330-1 6144 1024 13030
3340 6144 1024 8368
3350 6144 1024 19069
3375 8192 1024 35616
3380 6144 1024 47476
3390 6144 1024 56664
9345 6144 1024 46456
OTHER 6144 1024 56664

See Also


Chapter Contents
Previous
Next
Top of Page

Copyright 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.