Byte-addressable non-volatile memory(NVM),as a new participant in the storage hierarchy,gives extremely high performance in storage,which forces changes to be made on current filesystem designs.Page cache,once a signi...Byte-addressable non-volatile memory(NVM),as a new participant in the storage hierarchy,gives extremely high performance in storage,which forces changes to be made on current filesystem designs.Page cache,once a significant mechanism filling the performance gap between Dynamic Random Access Memory(DRAM)and block devices,is now a liability that heavily hinders the writing performance of NVM filesystems.Therefore state-of-the-art NVM filesystems leverage the direct access(DAX)technology to bypass the page cache entirely.However,the DRAM still provides higher bandwidth than NVM,which prevents skewed read workloads from benefiting from a higher bandwidth of the DRAM and leads to sub-optimal performance for the system.In this paper,we propose RCache,a readintensive workload-aware page cache for NVM filesystems.Different from traditional caching mechanisms where all reads go through DRAM,RCache uses a tiered page cache design,including assigning DRAM and NVM to hot and cold data separately,and reading data from both sides.To avoid copying data to DRAM in a critical path,RCache migrates data from NVM to DRAM in a background thread.Additionally,RCache manages data in DRAM in a lock-free manner for better latency and scalability.Evaluations on Intel Optane Data Center(DC)Persistent Memory Modules show that,compared with NOVA,RCache achieves 3 times higher bandwidth for read-intensive workloads and introduces little performance loss for write operations.展开更多
Limited Devonian magmatic record in northern West Junggar leads to contrasting models on its tectonic evolution.In this study,we conducted LA-ICP-MS U-Pb dating on detrital zircons of two sandstones from the Hebukesai...Limited Devonian magmatic record in northern West Junggar leads to contrasting models on its tectonic evolution.In this study,we conducted LA-ICP-MS U-Pb dating on detrital zircons of two sandstones from the Hebukesaier Formation in the Shaerbuerti Mountains.Detrital zircons with oscillatory zoning are characterized by high Th/U(>0.3)and low La/Yb(<0.15),indicating their magmatic origin.The youngest zircon ages of two samples are 402±2 Ma and 406±2 Ma,respectively,suggesting that the Hebukesaier Formation was deposited at the Early Devonian.Detrital zircon age patterns show single peaks(at ca.424 Ma,n=157),which indicates that these clastics were likely proximal accumulation after short distance transportation.Provenance of the Hebukesaier Formation was the Xiemisitai and Shaerbuerti Mountains.Detrital zircon ages range from 481 Ma to 395 Ma,which indicates that there was relatively continuous Early Paleozoic magmatism in the Xiemisitai and Shaerbuerti Mountains since the Early Ordovician.Age spectrums of sampled detrital zircons are distinct from those of Lower Devonian strata either in southern West Junggar or in East Junggar,which implies for individual tectonic evolution of northern West Junggar.We favor that Lower Devonian Hebukesaier Formation was developed in a fore–arc setting due to the northward subduction of the Junggar–Balkhash Ocean.展开更多
Cloud computing faces a series of challenges,such as insufficient bandwidth,unsatisfactory real-time,privacy protection,and energy consumption.To overcome the challenges,edge computing emerges.Edge computing refers to...Cloud computing faces a series of challenges,such as insufficient bandwidth,unsatisfactory real-time,privacy protection,and energy consumption.To overcome the challenges,edge computing emerges.Edge computing refers to a process where the open platform that converges the core capabilities of networks,computing,storage,and applications provides intelligent services at the network edge near the source of the objects or data to meet the critical requirements for agile connection,real-time services,data optimization,application intelligence,security and privacy protection of industry digitization.Edge computing consists of three elements:edge,computing,and intelligence.Edge computing and the Internet of Things(IoT)mutually create,and edge computing and cloud computing complement each other.In the architecture of edge computing,resources are distributed to the edge nodes,and therefore the storage system is near users while the computation function is near data.In this way,the stress on the backbone network can be lessened.With this architecture,the existing key technologies for computation,networks,and storage will change significantly.ZTE’s edge computing solutions can ensure the service quality of operators and greatly enhance the experience of mobile users.展开更多
Data layout in a file system is the organization of data stored in external storages. The data layout has a huge impact on performance of storage systems. We survey three main kinds of data layout in traditional file ...Data layout in a file system is the organization of data stored in external storages. The data layout has a huge impact on performance of storage systems. We survey three main kinds of data layout in traditional file systems： in-place update file system, log-structured file system, and copy-on-write file sys- tem. Each file system has its own strengths and weaknesses under different circumstances. We also include a recent us- age of persistent layout in a file system that combines both flash memory and byte- addressable non- volatile memory. With this survey, we conclude that persistent data layout in file systems may evolve dramatically in the era of emerging non-volatile memory.展开更多
基金supported by ZTE Industry⁃University⁃Institute Coopera⁃tion Funds under Grant No.HC⁃CN⁃20181128026.
文摘Byte-addressable non-volatile memory(NVM),as a new participant in the storage hierarchy,gives extremely high performance in storage,which forces changes to be made on current filesystem designs.Page cache,once a significant mechanism filling the performance gap between Dynamic Random Access Memory(DRAM)and block devices,is now a liability that heavily hinders the writing performance of NVM filesystems.Therefore state-of-the-art NVM filesystems leverage the direct access(DAX)technology to bypass the page cache entirely.However,the DRAM still provides higher bandwidth than NVM,which prevents skewed read workloads from benefiting from a higher bandwidth of the DRAM and leads to sub-optimal performance for the system.In this paper,we propose RCache,a readintensive workload-aware page cache for NVM filesystems.Different from traditional caching mechanisms where all reads go through DRAM,RCache uses a tiered page cache design,including assigning DRAM and NVM to hot and cold data separately,and reading data from both sides.To avoid copying data to DRAM in a critical path,RCache migrates data from NVM to DRAM in a background thread.Additionally,RCache manages data in DRAM in a lock-free manner for better latency and scalability.Evaluations on Intel Optane Data Center(DC)Persistent Memory Modules show that,compared with NOVA,RCache achieves 3 times higher bandwidth for read-intensive workloads and introduces little performance loss for write operations.
基金supported by the National Science Foundation of China(grants 41672217)the Fundamental Research Funds for the Central Universities(grants N2001004 and N2001021)State Scholarship Fund(grants 201806085034)。
文摘Limited Devonian magmatic record in northern West Junggar leads to contrasting models on its tectonic evolution.In this study,we conducted LA-ICP-MS U-Pb dating on detrital zircons of two sandstones from the Hebukesaier Formation in the Shaerbuerti Mountains.Detrital zircons with oscillatory zoning are characterized by high Th/U(>0.3)and low La/Yb(<0.15),indicating their magmatic origin.The youngest zircon ages of two samples are 402±2 Ma and 406±2 Ma,respectively,suggesting that the Hebukesaier Formation was deposited at the Early Devonian.Detrital zircon age patterns show single peaks(at ca.424 Ma,n=157),which indicates that these clastics were likely proximal accumulation after short distance transportation.Provenance of the Hebukesaier Formation was the Xiemisitai and Shaerbuerti Mountains.Detrital zircon ages range from 481 Ma to 395 Ma,which indicates that there was relatively continuous Early Paleozoic magmatism in the Xiemisitai and Shaerbuerti Mountains since the Early Ordovician.Age spectrums of sampled detrital zircons are distinct from those of Lower Devonian strata either in southern West Junggar or in East Junggar,which implies for individual tectonic evolution of northern West Junggar.We favor that Lower Devonian Hebukesaier Formation was developed in a fore–arc setting due to the northward subduction of the Junggar–Balkhash Ocean.
文摘Cloud computing faces a series of challenges,such as insufficient bandwidth,unsatisfactory real-time,privacy protection,and energy consumption.To overcome the challenges,edge computing emerges.Edge computing refers to a process where the open platform that converges the core capabilities of networks,computing,storage,and applications provides intelligent services at the network edge near the source of the objects or data to meet the critical requirements for agile connection,real-time services,data optimization,application intelligence,security and privacy protection of industry digitization.Edge computing consists of three elements:edge,computing,and intelligence.Edge computing and the Internet of Things(IoT)mutually create,and edge computing and cloud computing complement each other.In the architecture of edge computing,resources are distributed to the edge nodes,and therefore the storage system is near users while the computation function is near data.In this way,the stress on the backbone network can be lessened.With this architecture,the existing key technologies for computation,networks,and storage will change significantly.ZTE’s edge computing solutions can ensure the service quality of operators and greatly enhance the experience of mobile users.
基金supported by ZTE Industry-Academia-Research Cooperation Funds
文摘Data layout in a file system is the organization of data stored in external storages. The data layout has a huge impact on performance of storage systems. We survey three main kinds of data layout in traditional file systems： in-place update file system, log-structured file system, and copy-on-write file sys- tem. Each file system has its own strengths and weaknesses under different circumstances. We also include a recent us- age of persistent layout in a file system that combines both flash memory and byte- addressable non- volatile memory. With this survey, we conclude that persistent data layout in file systems may evolve dramatically in the era of emerging non-volatile memory.
