PORTABLE ELECTRONIC DEVICE HAVING A LOG-STRUCTURED FILE SYSTEM IN FLASH MEMORY

摘要

A portable electronic device includes a log-structured file system implementedin flashmemory. The log-structured file system includes a write function for storingcontiguous data recordsto the flash memory in the form of at least one data log, although the systemmay write data recordsto the flash memory using a plurality of data logs. The log-structured filesystem also includes a readfunction for retrieving data records from the one or more logs using aplurality of memory mappedpointers, which may be stored in an associated RAM index, or which may beimplemented as an indexstored in the flash memory. A clean-log function is also provided foreliminating inactive recordsfrom the log so that new data can be appended to the end of the log. Thevarious functionsassociated with the log-structured file system are implemented as at leastthree software modules, aread module, a write module and a clean-log module, although otherconfigurations are possible. Theportable electronic device may include a two-way RF transceiver for sendingand receiving data fromthe device, and may also include a plurality of application programs that areconfigured to interactwith the log-structured file system, as well as other software modules forcontrolling the operationof the portable electronic device.