Abstract: A data query apparatus, method, and storage medium include a database system that determines a data collection and a calculating model corresponding to a received query task request, according to the number of bytes occupied when the data collection or the calculating model is stored, or the number of bit widths occupied when the data collection or the calculating model is transmitted, the database system determines a transmission rate of the data collection or the calculating model. The query task request is transmitted to a model node or a data node with a lower transmission rate, and the data node or the model node with a higher transmission rate is dispatched to perform data calculation.

Abstract: The present invention provides a DRAM/NVM hierarchical heterogeneous memory system with software-hardware cooperative management schemes. In the system, NVM is used as large-capacity main memory, and DRAM is used as a cache to the NVM. Some reserved bits in the data structure of TLB and last-level page table are employed effectively to eliminate hardware costs in the conventional hardware-managed hierarchical memory architecture. The cache management in such a heterogeneous memory system is pushed to the software level. Moreover, the invention is able to reduce memory access latency in case of last-level cache misses. Considering that many applications have relatively poor data locality in big data application environments, the conventional demand-based data fetching policy for DRAM cache can aggravates cache pollution.

Abstract: The present invention provides a DRAM/NVM hierarchical heterogeneous memory system with software-hardware cooperative management schemes. In the system, NVM is used as large-capacity main memory, and DRAM is used as a cache to the NVM. Some reserved bits in the data structure of TLB and last-level page table are employed effectively to eliminate hardware costs in the conventional hardware-managed hierarchical memory architecture. The cache management in such a heterogeneous memory system is pushed to the software level. Moreover, the invention is able to reduce memory access latency in case of last-level cache misses. Considering that many applications have relatively poor data locality in big data application environments, the conventional demand-based data fetching policy for DRAM cache can aggravates cache pollution.