Abstract: Described are embodiments of an invention for allocating storage space in a storage system for critical data sets. The computing environment includes at least one server including a processor and memory. The server is coupled to storage. The memory further includes a storage manager including an allocation module and an alert module. The storage manager defines a common area for storing non-critical data sets and critical data sets in the storage group. The storage manager also defines a critical reserve area for storing only critical data sets in the first storage group. A predefined percentage of available storage space is reserved for the critical reserve area. The predefined percentage of available space is determined by comparing the available storage space within the critical reserve area to the storage space in the storage group.

Abstract: An apparatus, system, and method are disclosed for modifying data set names. A communication module receives a data set name as an index of a catalog entry for a catalog. The data set name comprises at least two qualifiers. A modification module modifies at least one data set name qualifier using a naming algorithm, wherein an alias qualifier is not modified. A store module stores the catalog entry indexed with the modified data set name in order to optimize the location of that entry within the catalog.

Abstract: Various method and system embodiments for facilitating catalog sharing in multiprocessor systems use multiple ECS cache structures to which catalogs are assigned based on an attribute such as SMS storage class or a high level qualifier (HLQ) (e.g. an N-to-1 mapping) or each individual catalog (e.g. a 1-to-1 mapping). When maintenance is performed on an ECS shared catalog, the multiple ECS cache structure requires only those catalogs associated with a particular ECS cache structure be disconnected. Any catalogs in the structure that are not involved in or affected by the maintenance may be temporarily or permanently moved to a different ECS cache structure. As a result, VVDS sharing is only required for those catalogs on which maintenance is being performed or that remain associated with that ECS cache structure during maintenance. This reduces I/O activity to the DASD, and results in a significant overall performance improvement.

Abstract: A method for selectively generating trace data is disclosed. Such a method includes executing a first module on a processor. The processor is operably coupled to a memory storing the first module and one or more branch modules. The method further includes detecting the execution of an instruction of the first module to execute a branch module. In response to detecting execution of the instruction, traces of branch modules subsequently executed by the processor are generated. Upon detecting a return of execution by the processor to the first module, the generation of traces is terminated and a trace report is generated. A corresponding apparatus and computer program product are also disclosed herein.

Abstract: Generation of diagnostic information of a computer-implemented system is made early so that the data is closer to the causation of errors or for performance analysis. At least one selected activity of the system is monitored from initiation of the activity, and the monitoring is for successful completion. Early collection of diagnostic information is provided by comparing the time of the activity without successful completion to an initial trigger, where the initial trigger is less than the time period for a time-out for the activity. If the time of the activity without successful completion exceeds the initial trigger, diagnostic information is collected and an initial dump of the diagnostic information is taken. In one example, a notification that the dump of diagnostic information has been taken is directed to the host or diagnostic terminal.

Abstract: A method to dynamically adjust the amount of free space in a storage group is disclosed herein. In certain embodiments, such a method may include monitoring the amount of free space in an active storage group. The method may further include maintaining an overflow storage group containing unused volumes. When the free space in the active storage group falls below a lower threshold value, the method may automatically move a volume from the overflow storage group to the active storage group. Conversely, when the free space in the active storage group exceeds an upper threshold value, the method may automatically transfer data from a volume in the active storage group to other volumes in the active storage group, and move the volume from the active storage group to the overflow storage group. A corresponding computer program product and apparatus are also disclosed herein.

Abstract: A data structure maintained in a computational device stores how many control areas splits have occurred to store a data set, wherein each control area split causes an addition of a single new control area. A command is received to add a new data record to the data set. A determination is made as to whether adding the new data record to the data set will result in a threshold for control area splits to be exceeded. In response to determining that adding the new data record to the data set will result in the threshold for control area splits to be exceeded, creating at least two new control areas in addition to continuing to use one existing control area for storing the data set.

Abstract: A data structure maintained in a computational device stores how many control areas splits have occurred to store a data set, wherein each control area split causes an addition of a single new control area. A command is received to add a new data record to the data set. A determination is made as to whether adding the new data record to the data set will result in a threshold for control area splits to be exceeded. In response to determining that adding the new data record to the data set will result in the threshold for control area splits to be exceeded, creating at least two new control areas in addition to continuing to use one existing control area for storing the data set.

Abstract: A data structure maintained in a computational device stores how many control areas splits have occurred to store a data set, wherein each control area split causes an addition of a single new control area. A command is received to add a new data record to the data set. A determination is made as to whether adding the new data record to the data set will result in a threshold for control area splits to be exceeded. In response to determining that adding the new data record to the data set will result in the threshold for control area splits to be exceeded, creating at least two new control areas in addition to continuing to use one existing control area for storing the data set.

Abstract: A plurality of catalogs are maintained, and wherein each catalog of the plurality of catalogs includes data sets and attributes of the data sets. An indication that a new data set is to be defined is received. A selected catalog is determined from the plurality of catalogs, wherein the selected catalog is suitable for including the new data set and attributes of the new data set. An entry that indicates a data set name corresponding to the new data set and an index to the selected catalog is inserted in a group table.

Abstract: Method, system, and computer program product embodiments of a time-based trace facility for facilitating software debugging without interfering with the run-time behavior, performance or resource usage of the traced software are provided. The trace facility resides in a different address space than the target address space and uses different time-slices of CPU resources to execute the instructions in the address spaces. The trace facility uses a cross-memory mode to read the state data from the target address space in accordance with a time schedule. The trace facility writes the state data to a trace area, which may be located in either the target or trace address spaces or external storage. With this approach, the trace facility can read a large amount of state data frequently to construct the type of historical record needed to analysis run-time behavior, performance and resource usage.

Abstract: A method, system, and computer program product for performing a backup operation in a computing environment is provided. A dataset corresponding to a backup copy is examined to determine if the dataset has changed from a previous backup operation. If the dataset has not changed, a backup inventory registry is consulted to determine a current version of a backup copy. The current version is one of a plurality of available versions. The backup operation is performed using the current version of the backup copy.

Abstract: A central hub is coupled to a plurality of computational devices. The central hub stores a data structure that grants locks for accessing common data stored at the central hub, wherein the common data is shared by the plurality of computational devices. Each computational device maintains locally those locks that are held by the computational device in the data structure stored at the central hub. In response to a failure of the data structure stored at the central hub, a selected computational device of the plurality of computational devices is determined to be a manager system. Other computational devices besides the manager system communicate to the manager system all locks held by the other computational devices in the data structure stored at the central hub. The data structure and the common data are generated and stored at the manager system. Transactions are performed with respect to the data structure stored at the manager system, until the data structure stored at the central hub is operational.

Abstract: A method for reorganizing a catalog to improve I/O performance includes initially placing a shared lock on a source catalog. The method then makes a point-in-time copy of the source catalog to generate a target catalog. Once the target catalog is generated, the method reorganizes the contents of the target catalog. Optionally, while reorganizing the contents of the target catalog, the method temporarily releases the shared lock on the source catalog and mirrors I/O intended for the source catalog to a buffer. The buffered I/O may then be used to update the target catalog to bring it current with the source catalog. When the target catalog is reorganized and up-to-date, the method upgrades the shared lock on the source catalog to an exclusive lock, overwrites the source catalog with the target catalog, and releases the exclusive lock. A corresponding apparatus and computer program product are also disclosed and claimed herein.

Abstract: An apparatus, system, and method are disclosed for analyzing code paths. In one embodiment, a starting point for one or more code paths within a listing of code is specified. The starting point may include code from which one or more code paths flow. An ending point is also specified for one or more code paths within the code, wherein the ending point includes code that is reachable via one or more of the code paths flowing from the starting point. Each code path flowing from the starting point to the ending point is determined by analyzing the listing of code without execution of the code. Information about the determined code paths is provided to a user.

Abstract: A method for identifying records of variable length within a data block containing corrupted data is disclosed herein. In certain embodiments, such a method may include scanning backward from an end of a data block containing variable-length records. The backward scan may proceed, one record at a time, to identify a first span of good (i.e., non-corrupt) records. The method may further include scanning forward from a front of the data block, also proceeding one record at a time, to identify a second span of good records. The method may include identifying a problem region by identifying data that resides between the first span and the second span. The method may also include creating a new record between the first span and the second span that contains the problem region. A corresponding computer program product, apparatus, and system are also disclosed.

Abstract: A directory and members are allocated to store a data set, wherein the directory stores pointers to the members to allow data stored in the members to be accessed. The directory is expanded to accommodate an expansion of the data set, causing the directory to be stored in non-contiguous pages and becoming fragmented. A computational device determines that a threshold that measures a level of fragmentation of the directory relative to an amount of storage allocated for the data set has been exceeded. The computational device reorganizes the fragmented directory, into a reorganized directory that is stored in contiguous pages at the end of the data set, in response to determining that the threshold has been exceeded.

Abstract: A directory and members are allocated to store a data set, wherein the directory stores pointers to the members to allow data stored in the members to be accessed. The directory is expanded to accommodate an expansion of the data set, causing the directory to be stored in non-contiguous pages and becoming fragmented. A computational device determines that a threshold that measures a level of fragmentation of the directory relative to an amount of storage allocated for the data set has been exceeded. The computational device reorganizes the fragmented directory, into a reorganized directory that is stored in contiguous pages at the end of the data set, in response to determining that the threshold has been exceeded.

Abstract: A method, system, and computer program product for identifying an overlay of a data processing target structure in a computing environment is provided. At least one of examining a mapping macro for the target structure with a set of valid ranges, comparing the set of valid ranges with the target structure to identify a string of at least one first invalid value and a last invalid value and locate invalid regions of the target structure, and examining executable code associated with the target structure, comparing at least one unchanged module against at least one additional module exhibiting an overlay characteristic to identify the string of the at least one first invalid value and the last invalid value and locate invalid regions of the target structure, is performed.

Abstract: Provided are a method, system, and program for allocating data sets to a container data set. A container data set is allocated in a storage system. An entry is included in a file allocation catalog for the allocated container data set indicating an address range of data allocated to the container data set, wherein the file allocation catalog maps data sets to address ranges in the storage system. A virtual file allocation catalog for the container data set is generated. A request is received to allocate a data set. A determination is made as to whether the data set to allocate has a size less than a threshold size. An entry is included in the virtual file allocation catalog to allocate the data set in the address range of the container data set in response to determining that the data set to allocate size is less than the threshold size.