Some IBM® i system limits relate to save and
restore, such as limits for the size of a save file and the size of an object that can be saved.
Table 1. Save and restore limits
|Save and restore limits
|Maximum number of related objects that can be saved or restored in a single save
||Approximately 111 000
|Maximum number of related internal integrated file system objects that can be
saved in a single operation3
||Approximately 500 000
|Maximum number of unrelated internal database file objects in a library that
can be saved in a single operation1,6
||Approximately 5.5 million
|Maximum number of changed database file members in a library that can be saved
||Approximately 1 million
|Maximum number of names in a save or restore command specifying which objects or libraries to
include or exclude in the save or restore operation2
|Maximum number of concurrent save or restore operations
||Limited only by available machine resources
|Maximum size of an object that can be saved
||Approximately 2 TB
|Maximum size of a save file5
||Approximately 2 TB
|Maximum size of description data saved for a file or set of
related files 1,4
||Approximately 4 GB
|Maximum number of document library objects (DLO) that can be
restored to a single user auxiliary storage pool (ASP)
- All database file objects in a library that are related to each other by
dependent logical files or shared formats are considered to be related objects. Starting in V5R4,
all database files in a library that have referential constraints are considered to be related
objects when using the save-while-active function.
A database file object consists of one or more
internal objects. A maximum of approximately 500 000 related internal objects can be saved in a
single save operation. One internal object is saved for each database file object, along with the
following additional internal objects:
- If the physical file is not keyed, add 1 internal object per member.
- If the physical file is keyed, add 2 internal objects per member.
- If the physical file has unique or referential constraints, add 1 internal object per
- If the physical file has triggers, add 1 internal object for the file.
- If the physical or logical file has column level authorities, add 1 internal object for the
- If you use ACCPTH(*YES) on the save command, add 1 internal object for each logical file in the
- Using generic names to specify groups of objects or libraries can help avoid this limit. For the
LIB, OMITLIB and OMITOBJ parameters on save commands, you can use the Command User Space (CMDUSRSPC)
parameter to raise the limit to 32 767 simple or generic names.
- Example of related internal integrated file system objects are objects with multiple hard-coded
links or Java programs attached to a stream file.
Description data includes descriptions of files, formats, fields, members, and
access paths, as well as general object descriptions. It also includes intermediate source code such
as that generated by the SQL precompiler or REXX interpreter. If your save operation exceeds this
limit, you may need to save the data without saving logical file access paths, or you may need to
omit some files or members and save them in a separate operation.
A limit of 16 MB per file remains in effect for 6.1 and earlier releases. Objects with more than
16 MB descriptive data cannot be saved to a target release of 6.1 or earlier.
- A limit of 1 TB remains in effect for 5.4 and earlier releases. Save files larger
than 1 TB cannot be transmitted to or restored on systems running 5.4 or earlier releases.
- To activate this limit, create the following data area. CRTDTAARA
DTAARA(QSYS/QDBSR256M) TYPE(*CHAR) LEN(1)
The limit without this data area is approximately