Abstract: A method commences upon accessing a set of data items that describe computing nodes to be organized into failure-tolerant configuration. The failure-tolerant configuration is characterized by system availability characteristics such as a replication factor and such as a hierarchical distribution of computing nodes. Characteristics of the topology include boundaries that define two or more hierarchically-related availability domain levels. Computing nodes are situated within these boundaries. Instances of a target hierarchical availability domain level are sorted, and instances of a hierarchically lower availability domain level are also sorted to form a multi-level sort order of computing nodes. Computing entities are mapped onto the computing nodes by observing the multi-level sort order.

Abstract: A method commences upon accessing a set of data items that describe computing nodes to be organized into failure-tolerant configuration. The failure-tolerant configuration is characterized by system availability characteristics such as a replication factor and such as a hierarchical distribution of computing nodes. Characteristics of the topology include boundaries that define two or more hierarchically-related availability domain levels. Computing nodes are situated within these boundaries. Instances of a target hierarchical availability domain level are sorted, and instances of a hierarchically lower availability domain level are also sorted to form a multi-level sort order of computing nodes. Computing entities are mapped onto the computing nodes by observing the multi-level sort order.

Abstract: A method, system, and computer program product is disclosed for generating an ordered sequence from a predetermined sequence of symbols using protected interleaved caches, such as semaphore protected interleaved caches. The approach commences by dividing the predetermined sequence of symbols into two or more interleaved caches, then mapping each of the two or more interleaved caches to a particular semaphore of a group of semaphores. The group of semaphores is organized into bytes or machine words for storing the group of semaphores into a shared memory, the shared memory accessible by a plurality of session processes. Protected (serialized) access by the session processes is provided by granting access to one of the two or more interleaved caches only after one of the plurality of session processes performs a semaphore altering read-modify-write operation (e.g., a CAS) on the particular semaphore.

Abstract: A method, system, and computer program product is disclosed for generating an ordered sequence from a predetermined sequence of symbols using protected interleaved caches, such as semaphore protected interleaved caches. The approach commences by dividing the predetermined sequence of symbols into two or more interleaved caches, then mapping each of the two or more interleaved caches to a particular semaphore of a group of semaphores. The group of semaphores is organized into bytes or machine words for storing the group of semaphores into a shared memory, the shared memory accessible by a plurality of session processes. Protected (serialized) access by the session processes is provided by granting access to one of the two or more interleaved caches only after one of the plurality of session processes performs a semaphore altering read-modify-write operation (e.g., a CAS) on the particular semaphore.