SUMMARYThe paper presents a new open-source framework called KernelHive for multilevel parallelization of computations among various clusters, cluster nodes, and finally, among both CPUs and GPUs for a particular application. An application is modeled as an acyclic directed graph with a possibility to run nodes in parallel and automatic expansion of nodes (called node unrolling) depending on the number of computation units available. A methodology is proposed for parallelization and mapping of an application to the environment that includes selection of devices using a chosen optimizer, selection of best grid configurations for compute devices, optimization of data partitioning and the execution. One of possibly many scheduling algorithms can be selected considering execution time, power consumption, and so on. An easy-to-use GUI is provided for modeling and monitoring with a repository of ready-to-use constructs and computational kernels. The methodology, execution times, and scalability have been demonstrated for a distributed and parallel password-breaking example run in a heterogeneous environment with a cluster and servers with different numbers of nodes and both CPUs and GPUs. Additionally, performance of the framework has been compared with an MPI + OpenCL implementation using a parallel geospatial interpolation application employing up to 40 cluster nodes and 320 cores.

Purpose -The purpose of this paper is to describe the state of development of Polish digital libraries. Design/methodology/approach -The paper describes the establishment of the first digital library in Poland, the creation of the Wielkopolska Digital Library and other regional digital libraries. The organisational and technological solutions used by these libraries are described. Findings -The concept of a single central library and several dozen regional libraries has made possible the creation of more than 40 digital libraries and the establishment of wide co-operation among digital librarians. However, the passage to mass digitisation is still proving impossible at present. Originality/value -The situation in Poland indicates a clear necessity for the introduction of appropriate legal regulations to place digitisation among the charter objectives of large libraries.The awarding of small grants does not change the situation, and sometimes even makes it worse. Digital libraries have come into being in large numbers over the last few years; because some of them have been functioning for a number of years, much experience has been acquired. Now it is necessary to move on to the next stage -mass digitisation. Polish libraries are quite unprepared for this. Digitisation continues to be treated by libraries as an experimental rather than a fundamental activity.

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