*TYPE2 directories

 

The "root" (/), QOpenSys, and user-defined file systems (UDFS) in the integrated file system support the *TYPE2 directory format. The *TYPE2 directory format is an enhancement of the original *TYPE1 directory format.

The concept of *TYPE1 and *TYPE2 stream files is different from the concept of *TYPE1 and *TYPE2 directory formats. One does not relate to the other.

*TYPE2 directories have a different internal structure and different implementation than *TYPE1 directories.

The advantages of *TYPE2 directories are:

• Improved performance

• Improved reliability

• Added functionality

• In many cases, less auxiliary storage space

*TYPE2 directories improve file system performance over *TYPE1 directories, especially when creating and deleting directories.

*TYPE2 directories are more reliable than *TYPE1 directories. After a system abnormally ends, *TYPE2 directories are completely recovered unless there has been an auxiliary storage failure. *TYPE1 directories may require the use of the Reclaim Storage (RCLSTG) command in order to recover completely.

*TYPE2 directories provide the following added functionality:

• *TYPE2 directories support renaming the case of a name in a monocase file system (for example, renaming from A to a).

• An object in a *TYPE2 directory can have up to one million links compared to 32 767 links for *TYPE1 directories. This means you can have up to 1 million hard links to a stream file, and a *TYPE2 directory can contain up to 999 998 subdirectories.

• Using iSeries™ Navigator, the list of entries are automatically sorted in binary order when you open a directory that has the *TYPE2 format.

• Some new functions such as integrated file system scanning support are only available for objects in *TYPE2 directories.

Typically, *TYPE2 directories that have fewer than 350 objects require less auxiliary storage than *TYPE1 directories with the same number of objects. *TYPE2 directories with more than 350 objects are ten percent larger (on average) than *TYPE1 directories.

There are several ways to get *TYPE2 directories on your system:

• New System i™ platforms that are preinstalled with OS/400^® V5R2 or i5/OS^® V5R3, or later, have *TYPE2 directories. No conversion is needed for "root" (/), QOpenSys, and UDFSs in ASPs 1-32.

• If you install OS/400 V5R2 or i5/OS V5R3, or later, on a System i platform for the first time, the platform has *TYPE2 directories. No conversion is needed for "root" (/), QOpenSys, and UDFSs in ASPs 1-32.

• The V5R1 or V5R2 conversion utility is used to convert the file systems.

• If the UDFSs in an independent ASP have not yet been converted to the *TYPE2 format, they will be converted the first time that the independent ASP is varied on to a system installed with OS/400 V5R2 or i5/OS V5R3 or later.

• All other supported file systems except UDFSs on independent ASPs that are still using *TYPE1 directories are converted automatically by the system. This conversion begins after the installation of i5/OS V5R3 or later releases. It should not significantly impact your system activity.

To determine the directory format for the file systems on your system, use the Convert Directory (CVTDIR) command:

CVTDIR OPTION(*CHECK)

*TYPE2 directories are supported on OS/400 V5R2 or i5/OS V5R3 or later, but there are some differences from normal *TYPE2 directory support.

 

*TYPE2 directories in OS/400 V5R1 or V5R2

The "root" (/), QOpenSys, and user-defined file systems (UDFS) in the integrated file system support the *TYPE2 directory format in OS/400 V5R1, V5R2, and later.

The *TYPE2 directory format is an enhancement of the original *TYPE1 directory format. *TYPE2 directories have a different internal structure from *TYPE1 directories and provide improved performance and reliability.

If you have OS/400 V5R1 or V5R2, you can convert your directories to the *TYPE2 directory format using the appropriate conversion utility. Shortly after i5/OS V5R3 or a later release is installed, the conversion to *TYPE2 directories will automatically begin for any of the file systems that have not yet been converted to support *TYPE2 directories. Therefore, you might want to consider converting to the *TYPE2 directory format before installing a later version to avoid this automatic conversion.

The support for *TYPE2 directories in OS/400 V5R2 is available in the V5R2 iSeries Information Center through the Convert Directory (CVTDIR) command.

The support for *TYPE2 directories in OS/400 V5R1 is available through program temporary fixes (PTFs). The conversion utility is slightly different from the OS/400 V5R2 version. Refer to the informational APAR II13161 for complete documentation on *TYPE2 directories in V5R1. Use one of the following methods to access the APAR:

• Download the informational APAR to your system and view it. Use the following commands:

  SNDPTFORD PTFID((II13161))
  DSPPTFCVR LICPGM(INFOAS4) SELECT(II13161)

• Go to the Support for IBM System i

  Web site to view the informational APAR. See Problem Solving > Technical Databases > Authorized Program Analysis Reports (APARs) > V5R1 APARs > INFOAS400 - AS/400 Information > APAR number II13161.

 

Parent topic:

Directory

 

Related reference

Converting directories from *TYPE1 to *TYPE2

 

Related information

Reclaim Storage (RCLSTG) command
Convert Directory (CVTDIR) command