File system limits

This topic contains the values for the system limits that are related to file systems.

They include limits on the number of documents in a folder, the size of a document, and the size of a stream file, among others.

Table 1. File system limits
File system limits Value
Maximum number of libraries in the system part of the library list 15
Maximum number of libraries in the user part of the library list1 250
Maximum number of objects in a library Approximately 360 000
Maximum number of documents and folders (DLOs) in a user ASP 349 000
Maximum number of DLOs in a folder 65 510
Maximum size of a document 2 gigabytes - 1
Maximum cumulative number of objects across the "root" (/), QOpenSys, and user-defined file systems of ASPs 1 through 32 2 147 483 647
Maximum cumulative number of objects across the user-defined file systems for each Independent ASP 2 147 483 647
Start of changeMaximum cumulative number of user-defined file systems in ASPs 1 through 32 End of change Start of change2 147 483 647End of change
Maximum number of user-defined files systems in an Independent ASP Approximately 4000
Maximum number of directories in one *TYPE1 directory in the "root" (/), QOpenSys, or user-defined file systems 32 765
Maximum number of directories in one *TYPE2 directory in the "root" (/), QOpenSys, or user-defined file systems 999 998
Maximum number of *TYPE1 directory links for an object in the "root" (/), QOpenSys, or user-defined file systems 32 767
Maximum number of *TYPE2 directory links for an object in the "root" (/), QOpenSys, or user-defined file systems 1 000 000
Maximum size of a stream file 1 terabyte
Start of changeMaximum file size that can be read or written using the iSeries™ Access File ServerEnd of change Start of change4 gigabytesEnd of change
Default maximum number of file and socket descriptors per job2 200
Maximum number of file and socket descriptors per job 2 500 000
Maximums for directory levels, path names, and object attributes and links See the File System Comparison topic in the Information Center.
Maximum number of files that the iSeries Access File Server can have open at one time3 16 776 960
Maximum number of scan descriptors per job4 Approximately 524 000
Notes:
  1. There are compatibility considerations for application programs that retrieve library lists and are not prepared for the longer lists. For more details, see the V5R1 Memo to Users.
  2. Default can be changed with DosSetRelMaxFH() - Change the Maximum Number of File Descriptors (see UNIX-Type APIs in the Information Center.)
  3. This limit is cumulative across all File Server jobs (QPWFSxxxx and QZLSFILE jobs) on the system. Once a file is closed, it no longer counts toward the limit. Some applications that can be affected by this limit are iSeries Access, iSeries NetServer™, Network Station® boot up (which keeps over 200 files open, unless using Compact Flash Memory which only requires about 25 files) and applications, and the QFileSvr.400 file system.
  4. Start of changeFor more information about scan descriptors, see Integrated File System Scan on Open Exit Program in the API topic. End of change