!!! Welcome to KMR This is KMR, a high-performance map-reduce library. KMR-1.0 is available since 2013-04-26. KMR works on ordinary clusters as well as large-scale supercomputers. KMR source code is available under the BSD license. __Latest release is KMR-1.9 (2018-08-27)__. KMR is a set of high-performance map-reduce operations in the MPI (Message Passing Interface) environment. It makes programming for data-processing much easier by hiding low-level details of message passing. Its main targets are large-scale supercomputers with thousands of compute nodes. KMR provides utilities other than map-reduce operations to address issues such as accessing very large file-systems, on platforms K and Fujitsu FX10. KMR is designed to work in-memory and exploit large amount of memory available on supercomputers, whereas most map-reduce implementations are designed to work with external (disk-based) operations. So, data exchanges in KMR occur as message passing instead of remote file operations. The KMR routines work in bulk-synchronous and the most part of the code is sequential, but the code inside the mapper and reducer are multi-threaded. !!Documents * [Overview and API Document|https://riken-rccs.github.io/kmr/] ** It is a Doxgen generated document, included in the installation. !!Downloading * [Download] !!Tutorials * [Tutorial] (in Japanese) !!Project Site * KMR in GitHub [https://github.com/riken-rccs] * Issue reporting [https://github.com/riken-rccs/kmr/issues] * Other software from RIKEN R-CCS [https://riken-rccs.github.io] !!Publications * __K MapReduce: A Scalable Tool for Data-Processing and Search/Ensemble Applications on Large-Scale Supercomputers__. Motohiko Matsuda, Naoya Maruyama, and Shinichiro Takizawa. IEEE Cluster Computing (CLUSTER) 2013. (C) Copyright IEEE. [ieeexplore.ieee.org|https://ieeexplore.ieee.org/document/6702663]\\ It describes an overview and optimizations used in KMR. * __Supporting Workflow Management of Scientific Applications by MapReduce Programming Model__. Shinichiro Takizawa, Motohiko Matsuda, and Naoya Maruyama. IPSJ HPCS 2014. (in Japanese) [hpcs2014.pdf]\\ It describes some scientific applications workflow implemented in MapReduce using KMR. * __Evaluation of Asynchronous MPI Communication in Map-Reduce System on the K Computer__. Motohiko Matsuda, Naoya Maruyama, and Shinichiro Takizawa. EuroMPI Workshop 2014. (C) Copyright ACM. [dl.acm.org|https://dl.acm.org/doi/10.1145/2642769.2642800]\\ It compares all-to-all collective communication versus asynchronous communication in shuffling communication, to qualify believed effectiveness of overlapping of communication and computation. ---- !!Acknowledgment KMR is a product of RIKEN R-CCS. Part of the results is obtained by using K computer at RIKEN R-CCS. ---- !!DISCLAIMER KMR comes with ABSOLUTELY NO WARRANTY. This wiki also comes with ABSOLUTELY NO WARRANTY. Contents are liable to change.