Storage backends of parallel compute clusters are still based mostly on magnetic disks,while newer and faster storage technologies such as flash-based SSDs or non-volatile random access memory(NVRAM)are deployed withi...Storage backends of parallel compute clusters are still based mostly on magnetic disks,while newer and faster storage technologies such as flash-based SSDs or non-volatile random access memory(NVRAM)are deployed within compute nodes.Including these new storage technologies into scientific workflows is unfortunately today a mostly manual task,and most scientists therefore do not take advantage of the faster storage media.One approach to systematically include nodelocal SSDs or NVRAMs into scientific workflows is to deploy ad hoc file systems over a set of compute nodes,which serve as temporary storage systems for single applications or longer-running campaigns.This paper presents results from the Dagstuhl Seminar 17202"Challenges and Opportunities of User-Level File Systems for HPC"and discusses application scenarios as well as design strategies for ad hoc file systems using node-local storage media.The discussion includes open research questions,such as how to couple ad hoc file systems with the batch scheduling environment and how to schedule stage-in and stage-out processes of data between the storage backend and the ad hoc file systems.Also presented are strategies to build ad hoc file systems by using reusable components for networking and how to improve storage device compatibility.Various interfaces and semantics are presented,for example those used by the three ad hoc file systems BeeOND,GekkoFS,and BurstFS.Their presentation covers a range from file systems running in production to cutting-edge research focusing on reaching the performance limits of the underlying devices.展开更多
Many scientific fields increasingly use high-performance computing(HPC)to process and analyze massive amounts of experimental data while storage systems in today's HPC environments have to cope with new access pat...Many scientific fields increasingly use high-performance computing(HPC)to process and analyze massive amounts of experimental data while storage systems in today's HPC environments have to cope with new access patterns.These patterns include many metadata operations,small I/O requests,or randomized file I/O,while general-purpose parallel file systems have been optimized for sequential shared access to large files.Burst buffer file systems create a separate file system that applications can use to store temporary data.They aggregate node-local storage available within the compute nodes or use dedicated SSD clusters and offer a peak bandwidth higher than that of the backend parallel file system without interfering with it.However,burst buffer file systems typically offer many features that a scientific application,running in isolation for a limited amount of time,does not require.We present GekkoFS,a temporary,highly-scalable file system which has been specifically optimized for the aforementioned use cases.GekkoFS provides relaxed POSIX semantics which only offers features which are actually required by most(not all)applications.GekkoFS is,therefore,able to provide scalable I/O performance and reaches millions of metadata operations already for a small number of nodes,significantly outperforming the capabilities of common parallel file systems.展开更多
基金This work has also been partially funded by the German Research Foundation(DFG)through the German Priority Programme 1648"Software for Exascale Computing"(SPPEXA)and the ADA-FS project,and by the European Union's Horizon 2020 Research and Innovation Program under the NEXTGenIO Project under Grant No.671591the Spanish Ministry of Science and Innovation under Contract No.TIN2015-65316+3 种基金the Generalitat de Catalunya under Contract No.2014-SGR-1051This work was performed under the auspices of the U.S.Department of Energy by Lawrence Livermore National Laboratory under Contract No.DE-AC52-07NA27344(LLNL-JRNL-779789)also supported by the U.S.Department of Energy,Office of Science,Advanced Scientific Computing Research,under Contract No.DE-AC02-06CH11357This work is also supported in part by the National Science Foundation of USA under Grant Nos.1561041,1564647,1744336,1763547,and 1822737.
文摘Storage backends of parallel compute clusters are still based mostly on magnetic disks,while newer and faster storage technologies such as flash-based SSDs or non-volatile random access memory(NVRAM)are deployed within compute nodes.Including these new storage technologies into scientific workflows is unfortunately today a mostly manual task,and most scientists therefore do not take advantage of the faster storage media.One approach to systematically include nodelocal SSDs or NVRAMs into scientific workflows is to deploy ad hoc file systems over a set of compute nodes,which serve as temporary storage systems for single applications or longer-running campaigns.This paper presents results from the Dagstuhl Seminar 17202"Challenges and Opportunities of User-Level File Systems for HPC"and discusses application scenarios as well as design strategies for ad hoc file systems using node-local storage media.The discussion includes open research questions,such as how to couple ad hoc file systems with the batch scheduling environment and how to schedule stage-in and stage-out processes of data between the storage backend and the ad hoc file systems.Also presented are strategies to build ad hoc file systems by using reusable components for networking and how to improve storage device compatibility.Various interfaces and semantics are presented,for example those used by the three ad hoc file systems BeeOND,GekkoFS,and BurstFS.Their presentation covers a range from file systems running in production to cutting-edge research focusing on reaching the performance limits of the underlying devices.
基金This work has been funded by the German Research Foundation(DFG)through the Priority Programme 1648"Software for Exascale Computing"and the ADA-FS projectalso partially supported by the Spanish Ministry of Science and Innovation under Grant No.TIN2015-65316+1 种基金the Generalitat de Catalunya under Contract 2014-SGR-1051as well as the European Union's Horizon 2020 Research and Innovation Programme,under Grant Agreement No.671951(NEXTGenIO).
文摘Many scientific fields increasingly use high-performance computing(HPC)to process and analyze massive amounts of experimental data while storage systems in today's HPC environments have to cope with new access patterns.These patterns include many metadata operations,small I/O requests,or randomized file I/O,while general-purpose parallel file systems have been optimized for sequential shared access to large files.Burst buffer file systems create a separate file system that applications can use to store temporary data.They aggregate node-local storage available within the compute nodes or use dedicated SSD clusters and offer a peak bandwidth higher than that of the backend parallel file system without interfering with it.However,burst buffer file systems typically offer many features that a scientific application,running in isolation for a limited amount of time,does not require.We present GekkoFS,a temporary,highly-scalable file system which has been specifically optimized for the aforementioned use cases.GekkoFS provides relaxed POSIX semantics which only offers features which are actually required by most(not all)applications.GekkoFS is,therefore,able to provide scalable I/O performance and reaches millions of metadata operations already for a small number of nodes,significantly outperforming the capabilities of common parallel file systems.
