Fast/Unload overview

Fast/Unload is a utility which quickly unloads data from a Model 204 file to one or more sequential data sets. Fast/Unload consists of several functional units:

• A data extraction facility which reads data from a Model 204 file.
• A compiler which converts a special data language (FUEL) to machine language. The generated machine language performs the output function and other general-purpose manipulation.
• A reporting facility which provides a job log, job statistics, file statistics, and field statistics, and reports any special conditions or errors that might have occurred during a run.

Fast/Unload can either be invoked directly as a standalone load module or from a SOUL program. When invoked as a standalone load module, Fast/Unload enqueues the data file in share mode unless explicitly requested otherwise. If the enqueue fails, the Fast/Unload terminates with an error condition code. Therefore, you must ensure that when Fast/Unload is run as a standalone load module, Model 204 does not have the file enqueued in exclusive mode.

Note: As of version 4.6, Fast/Unload must be running under z/OS or z/VM CMS. As of version 4.7, Fast/Unload supports EAV (Extended Attribute Volume) disks for Model 204 files and supports FILEORG X'200' files.

Fast/Unload topics

The Fast/Unload documentation consists of the pages listed below. This list is also available as a "See also" link from each of the pages.

See also:

• The release notes for information about product changes and Model 204 feature support per Fast/Unload version.
• Fast/Unload messages for information about product error messages.

Fast/Unload topic list

• Fast/Unload overview
• Fast/Unload invocation
• Fast/Unload program parameters
• Fast/Unload Extraction Language (FUEL)
• Fast/Unload standard #functions
• Fast/Unload BLOB/CLOB processing considerations
• Fast/Unload datetime processing considerations
• Fast/Unload DATESTAT analysis
• Fast/Unload job statistics
• Fast/Unload SOUL Interface
• Fast/Unload with an external sort package
• Fast/Unload with DBCS data
• Fast/Unload customer-written assembler #function packages
• Fast/Unload user exits or filters
• Fast/Unload with Model 204 file groups
• Fast/Unload with Model 204 fieldgroups
• Fast/Unload with the Sir2000 Field Migration Facility
• Fast/Unload floating point arithmetic and numeric conversion
• Fast/Unload program return codes
• Fast/Unload installation
• Fast/Unload customization of defaults
• Fast/Unload SMF record format
• Fast/Unload release notes
• Fast/Unload messages

Fast/Unload SOUL Interface

The Fast/Unload SOUL Interface (FUSI), purchased as a separate Fast/Unload option, allows one to invoke Fast/Unload using the FastUnload or FastUnloadTask method of the Recordset class, or using the $Funload function in a SOUL program.

With this approach, an application builds a set of records to be unloaded, using standard User Language statements; for example, you can reduce unload time by restricting the set of records using indexed Model 204 fields. The Fast/Unload load module runs in a subtask (or PST under CMS) of Model 204. Since the unload is from a Model 204 record set, the Fast/Unload SOUL Interface automatically provides the ability to unload data from a Model 204 group; standalone Fast/Unload provides that functionality by allowing multiple Model 204 file names on the OPEN statement.

The Fast/Unload SOUL Interface processing can be synchronous or asynchronous.

A system manager can cancel or examine Fast/Unload requests, and each user can perform the same functions on asynchronous requests that he or she initiated.

Fast/Unload zIIP support

Support for offloading Model 204 work to zIIP processors is extended to Fast/Unload as of version 7.7 of Model 204.

Exploiting zIIPs in Fast/Unload requires:

1. z/OS, which is where the zIIP-accessing SRBs reside.
2. Customer authorization for the Fast/Unload HPO product, a Fast/Unload option.
3. Appropriate setting of zIIP and Fast/Unload Model 204 system parameters.
   • If Fast/Unload is invoked from FUSI, several Model parameters are of concern.
   • Otherwise (that is, PGM=FUNLOAD), new Fast/Unload parameters (non-FUSI-specifiable) are likely necessary.

Even if the Model 204 massive zIIP offload product is not purchased or in use, Fast/Unload HPO offers improved performance because it locates the Fast/Unload control blocks above the bar, taking advantage of the enhanced Model 204 V7.6 64-bit addressing and ATB storage.