In a online info storage program, cache storage area is used to accelerate sponsor access to a data data file. Adaptive throttling is used to manage the storage space subsystem, enabling the storage manager to delay business.
The virtual data storage area system contains a storage manager 31, a éclipse directory 22 and a plurality of storage volumes 62. Voile storage 20 is used to store premigrated documents. When a new data record is wanted by the hold processor, it is copied to the selected storage volume. During more info here the migration of an data record to the selected storage volume level, a «cache hit» occurs.
A storage supervisor controls the original premigration of information files and the subsequent migration. It also keeps reference details for the premigrated files. These include the logical volume level identifier (LVI) 44, a pointer for the data document and a storage volume level offset 46, which can be the position within just sequential media.
Coordinator processing devices, such as a mainframe or a computer, generate data and request a logical volume from the virtual info storage system. The data file is copied from disparition storage 20 to the storage volume. The moved files happen to be then recalled from the storage space subsystem.
To shield the capacity of the cache storage area, the storage area manager does the following input and output operations. Primary, the storage manager keeps track of the amount of free of charge space. If it drops under a threshold, it computes a throttle. This is an adjustment of performance that may be more significant over a cache space threshold.