Logical Files (Views) - Impact on Performance (I/O)

Hello Midrangers.

We recently implemented a new system on our IBM i720 (v6r1m0). Performance
is since negatively impacted and the bottle-neck is massively I/O related.
Disks are not keeping up.

Looking at the size of the systems database, it is 53% Logical Files
(Views).
All these views (LF's) were created (CRTLF) with the attribute FILETYPE =
DATA. (Most LF's reference a single Physical File only, not multiple PF's)
These LF's are occupying physical space on disk (53%... more than half the
actual database) and I'm concerned there is an I/O impact because of this
?

Can someone elaborate on what the FILETYPE = DATA setting does ? Is it
duplicating physical file data and possibly the source of severe I/O
activity ? (Whats the difference between data records and source records
?) Is there any best practice / recommendations re the use of LF's ?

CRTLF (Command - Create Logical File)

Attribute : File type (FILETYPE)
Specifies whether each member of the logical file being created contains
data records, or contains source records for a program or another file.
*DATA
The logical file contains data records.
*SRC
The logical file contains source records. This value cannot be specified
for join logical files.




Thanks,
G
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