Storage(Easy,2oolines) Arrange data on disk, in the form of Page Similarto Virtual Memory in OSHigh level layers only knows a Page ID as anentry point for access of the data
Arrange data on disk, in the form of Page Similar to Virtual Memory in OS High level layers only knows a Page ID as an entry point for access of the data
StorageMy ImplementationVirtual address space: 4GBSelf-grow page files:4MB eachAn advanced bitmap: segment treeMaininterfaces(All deal with file operations on disk)CreateDB,OpenDB,CloseDB,DestroyDBAllocatePage, DeallocatePageWritePage,ReadPage
My Implementation ▪ Virtual address space: 4GB ▪ Self-grow page files: 4MB each ▪ An advanced bitmap: segment tree ▪ Main interfaces (All deal with file operations on disk) ▪ CreateDB, OpenDB, CloseDB, DestroyDB ▪ AllocatePage, DeallocatePage ▪ WritePage, ReadPage
Buffer(Easy,3oolines) A traditional cache strategy, store frequentlyaccessed pages in memory (instead of in thedisk storage system)
A traditional cache strategy, store frequently accessed pages in memory (instead of in the disk storage system)
BufferMy implementationStore 2o48 frequently used pages 2nd-chance replacement algorithmMaininterfaces:AllocatePage, DeallocatePage GetPage (Handle page missing)ReleasePagePinPage, UnpinPage (Reference count)
My implementation ▪ Store 2048 frequently used pages ▪ 2nd-chance replacement algorithm ▪ Main interfaces: ▪ AllocatePage, DeallocatePage ▪ GetPage (Handle page missing) ▪ ReleasePage ▪ PinPage, UnpinPage (Reference count)
HeapFile(medium,iklines)provides the ability of sequential access ofthe records, as well as insertion, deletion,Updating and etc basic features.Manage table structuresManipulate tables in unit of tuple Generate iterators for upper layers The heap file defines the format of tablestructures and tuples in pages
provides the ability of sequential access of the records, as well as insertion, deletion, updating and etc basic features. Manage table structures Manipulate tables in unit of tuple Generate iteratorsfor upper layers The heap file defines the format of table structures and tuples in pages