Loading an SCA library is a time-consuming operation. Here are suggestions for reducing LOAD time: o Virtual I/O Cache facility SCA uses a large number of I/Os during LOAD. Disk caching can greatly reduce the number of I/Os, and improve performance. Your system manager can enable disk caching by setting the VBN_CACHE_S SYSGEN parameter. Use SHOW MEMORY/CACHE to see whether disk caching is enabled. o Batch loads Loading more than one module at a time is more efficient than loading modules separately. For example, use LOAD *.ANA. o Multiple libraries With large software systems, it is a good idea to use more than one SCA library and load them all simultaneously. This can decrease the elapsed LOAD time considerably, especially if the libraries are on separate disks. Using more than one CPU also helps, but not as dramatically, because SCA loading is mainly I/O intensive. For more information about how to use multiple libraries, see the help subtopics under Libraries. o Choice of Disk SCA uses a large number of I/Os during LOAD. Loading an SCA library on a slow, heavily used, or badly fragmented disk causes the load to be less efficient. o File Fragmentation and File Preallocation If your SCA library is larger than 20K blocks, you should consider preallocating the library when you create it. SCA extends the library file by 1000 blocks at a time, so for large libraries it extends the library many times, and this may cause your SCA library to be badly fragmented. Preallocate an SCA library with CREATE LIBRARY/SIZE=xxx, where xxx is the size of the library in disk blocks. Use the size of the SCA$EVENT.DAT file in your current SCA library directory as the value to the /SIZE qualifier. You can tell how badly your SCA libraries are fragmented by using the following command: $ DUMP/HEADER/BLOCK=COUNT=0 - _$ DISK:[sca_library_directory]SCA$EVENT.DAT The interesting portion of the output is the Map area. Each retrieval pointer represents a contiguous section on the disk. Because SCA extends SCA libraries 1000 blocks at a time, having a lot of retrieval pointers smaller than this is a strong indication that some defragmentation is needed. o Using less disk space Use LOAD/DELETE to delete .ANA files after they are successfully loaded. This doesn't reduce LOAD time, but uses less disk space.