KV-cache 1 KV-cache Fig.1 WorkflowofKV-cache 2.2 Key-value Key ; Key Mem-cache (FIFO) Value Value Key Mem-cache ( Value 256B 100 MB 20%

Size: px

Start display at page:

Download "KV-cache 1 KV-cache Fig.1 WorkflowofKV-cache 2.2 Key-value Key ; Key Mem-cache (FIFO) Value Value Key Mem-cache ( Value 256B 100 MB 20%"

滢黎
7 years ago
Views:

1 GeomaticsandInformationScienceofWuhanUniversity Vol.38No.11 Nov.2013 : (2013) :A GIS Key-value ( ) : 设计了一种基于 Key-value 结构的缓存 KV-cache 旨在简化数据结构高效管理缓存数据 KV-cache 由 Mem-cache 和 F-cache 构成其中 Mem-cache 为第一级缓存并采用缓存回写机制以异步方式将数据写入 F-cache 进行持久化存储 F-cache 使用大文件存储数据并构建了基于 B 树的缓存索引以加快检索速度数据写入 F-cache 的位置由基于 B 树的空闲空间管理器进行分配在 100 Mbps 局域网内测试 KV-cache 读写性能实验表明 KV-cache 读写性能优于传统文件目录方式的缓存能够安全高效地管理所缓存的各种空间数据 : 分布式 GIS; 缓存 ;KV-cache;Key-value 存储 ; 空闲空间管理 :P208;TP GIS (Key) (Value) Value GIS ;Key [1-2] Key-value [3-5] GIS [11-12] Key-value Key-value GIS Bigtable [12] Dynamo [11] Cas- sandra [13] Key-value GIS [3-9] NASA World Wind [410] 2.1 I/O (KV-cache) Key- [4] value Key-value GIS DEM KV-cache 1 Key-value 2 (Mem-cache) (F-cache) Mem- cache F-cache F-cache ;F-cache Key-value : : ( ); (2011BAH16B08)

1340 2013 11 1 KV-cache 1 KV-cache Fig.1 WorkflowofKV-cache 2.2 Key-value Key ; Key Mem-cache (FIFO) Value Value Key Mem-cache ( Value 256B 100 MB 20%) F- cache Key-value 2.

2 KV-cache 1 KV-cache Fig.1 WorkflowofKV-cache 2.2 Key-value Key ; Key Mem-cache (FIFO) Value Value Key Mem-cache ( Value 256B 100 MB 20%) F- cache Key-value 2.4 (F-cache) Key Value F-cache F-cache ; 8 ; 64 ; Value 3 F-cache Fig.3 SchematicDiagramofF-cacheStructure B Oracle MySQL B GB 2.3 (Mem-cache) Mem-cache F-cache F- cache I/O Mem-cache B : Key Mem-cache Key Mem-cache F-cache 2 Fig.2 ASampleofCachingImagePyramid

38 11 : GIS Key-value 1341 WindowsXP 90 m F- SRTM 10 cache 512 512 jpg 700975 8.57GB F-cache 5~154 KB 5 3 64 B 4 F-cache ; 5 SRTM ; Fig.

3 38 11 : GIS Key-value 1341 WindowsXP 90 m F- SRTM 10 cache jpg GB F-cache 5~154 KB B 4 F-cache ; 5 SRTM ; Fig.5 RenderingSRTMImagePyramidintheClient C# ( ) KV- cache F-cache 1GB 5minKV-cache Mem-cache KV-cache 4 F-cache ; Mem-cache Fig.4 SchematicDiagramofWritingCache KV-cache BlocktoF-cacheUnderSeveralConditions F-cache F-cache 2 3 SRTM 50 MB 6 KV-cache F- cache 6(a) KV-cache F-cache 5min 10min 15min 20min 25min 30min Mem-cacheKV-cache F-cache 6(b) C# 100Mbps 6 C/S Fig.6 AverageRead/WriteTimeofDiferentCaches :CPU AMDPhenom IX49554 GB 1TB WindowsServ- er2003; :CPU Intel Dual E22002 GB 500 GB 7 KV- cache 7(a) Mem- cache

4 KV-cache 15min KV-cache 5min KV-cache 2min ; 15 min GIS KV-cache 7(b) Mem-cache [1]. [M].2. : KV-cache 20094:55-59 Fig.7 AverageRead/WriteElapsedTimeofKV-cache withdiferenttimingintervals (12): KV-cache Mem-cache [6]. 8(a) 5 [J]. ( min Mem-cache )20099:37-39 [7] YangC WWong W DYangR Xetal.Perform- Mem-cache ance-improvingtechniquesin Web-based GIS[J]. InternationalJournalof GeographicalInformation F-cache Science200519(3): [8]. P2P 8(b) [J] :236- Mem- 241 cache KV-cache [9]. WebGIS [J] : Fig Mem-cache KV-cache AverageRead/WriteTimeofKV-cachein DiferentMem-cacheCapacities StructuredStorageSystem[J].ACM SIGOPS Op- DPGrid C/S eratingsystemsreview201044(2):35-40 DPGrid : KV-cache [email protected] KV-cache [2]. (QoGIS): [J] (5): [3]. WebGIS [J] :41-44 [4]. 3 [J]. [5].WebGIS [J]. wind.arc.nasa.gov/index.html2011 [10]NASA.NASA World Wind[OL].htp://world- [11]DecandiaGHastorunDJampaniMetal.Dyna- mo:amazon s Highly Available Key-valueStore [J]. ACM SIGOPS Operating Systems Review (6): [12]ChangFDeanJGhemawatSetal.Bigtable:A DistributedStorageSystemforStructuredData[J]. ACM TransactionsonComputerSystems(TOCS) (2):1-26 [13]LakshmanAMalikP.Cassandra -A Decentralized GIS

5 38 11 : GIS Key-value 1343 Key-valueCachingofGeospatialDataforDistributedGIS TU Zhenfa 1 MENG Lingkui 1 ZHANG Wen 1 HUANG Changqing 1 (1 SchoolofRemoteSensingandInformationEngineeringWuhanUniversity129LuoyuRoadWuhan430079China) Aboutthefirstauthor:TUZhenfaPhDcandidatespecializedinspatialdatastorageandmanagementcloudGISetc. [email protected] 檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪檪 ( 上接第 1338 页 ) LocalTerrainDeformationinPanoramicMaps LI Lin 1 YU Zhonghai 1 LI Zhen 1 XIANG Zhujun 2 (1 SchoolofResourceandEnvironmentalSciencesWuhanUniversity129LuoyuRoadWuhan430079China) (2 Troops61363Xi an710054china) Abstract:Theaccessandnetworktransmissioncostsforgeospatialdataindistributed GIS areimportantfactorsefectingperformance.thecacheisoneoftheefective measuresto solveperformanceproblems.inthispaperwedesignedacachenamed KV-cachebasedon Key-valuestructureto managegeospatialdataeficiently withasimpledatastructure.a KV-cacheconsistsofamemorycachecaled Mem-cacheandafilecachecaledF-cache.Mem- cacheisthefirstlevelcachethecachewrite-back mechanism guaranteesthatdataisbeing writentothef-cacheasynchronously.thef-cacheiscreatedbyasinglelargefilewhilea cacheindexerbasedonb-treeisbuilttospeedupthequery.afreespacemanagerwhichis alsobasedonb-treeisusedtoalocatethedatastorageaddressforf-cache.experiments comparetheread/writeperformanceofkv-cachewiththetraditionalfilecacheinthe100 MbpsLAN.Theexperimentsshowthattheread/writeperformanceofKV-cacheis much beterthanfilecachethusmanaginggeospatialdatamoresecurelyandeficiently. Keywords:distributedGIS;cache;KV-cache;Key-valuestorage;freespacemanager Abstract:Panoramicmapsareusualyusedtoshowthelandscapefrom aspecificdirection and viewing heightin acentralperspective projection.regardless ofthe direction and heightsomelandscapefeatures maybeobscured.inordertoimprovethevisualefectof panoramicmapsamethodforlocalterraindeformationinthehorizontaldirectionbasedon liquefactiondeformationisproposed.this methodforreducinglocalterrainelevationis basedoneyetrackingamethodthatraisesthelocalterrainelevationusingagaussiantrans- form.thismethodreducesocclusionandshrinkagephenomenonenhancingtheartisticvis- ualefectsofapanoramicmap. Keywords:panoramic maps;localterrain distortion;liquefaction deformation;gaussian transform;gazetracking Aboutthefirstauthor:LILinprofessorPhDsupervisor.Heisengagedincartographygeo-ontologyand3Dcadaster. [email protected]

附件：2013-2014学年华南师范大学共青团工作先进集体和优秀个人名单

附件：2013-2014学年华南师范大学共青团工作先进集体和优秀个人名单关于表彰 2013 2014 学年华南师范大学共青团工作先进集体和优秀个人的决定各二级团组织 : 一年来, 我校各级团组织在团省委和校党委的正确领导下, 积极贯彻落实党的十八大精神, 狠抓共青团思想建设队伍建设和作风建设, 推动团