00001 ////////////////////////////////////////////////////////////////////////// 00002 // // 00003 // XrdClientReadAhead // 00004 // // 00005 // Author: Fabrizio Furano (CERN IT-DM, 2009) // 00006 // // 00007 // Classes to implement a selectable read ahead decision maker // 00008 // // 00009 ////////////////////////////////////////////////////////////////////////// 00010 00011 // $Id: XrdClientReadAhead.hh 30949 2009-11-02 16:37:58Z ganis $ 00012 00013 #ifndef XRD_CLI_READAHEAD 00014 #define XRD_CLI_READAHEAD 00015 00016 00017 00018 class XrdClientReadAheadMgr { 00019 public: 00020 enum XrdClient_RAStrategy { 00021 RAStr_none, 00022 RAStr_pureseq, 00023 RAStr_SlidingAvg 00024 }; 00025 00026 protected: 00027 long RASize; 00028 XrdClient_RAStrategy currstrategy; 00029 00030 public: 00031 00032 static XrdClientReadAheadMgr *CreateReadAheadMgr(XrdClient_RAStrategy strategy); 00033 00034 00035 XrdClientReadAheadMgr() { RASize = 0; }; 00036 virtual ~XrdClientReadAheadMgr() {}; 00037 00038 virtual int GetReadAheadHint(long long offset, long len, long long &raoffset, long &ralen, long blksize) = 0; 00039 virtual int Reset() = 0; 00040 virtual void SetRASize(long bytes) { RASize = bytes; }; 00041 00042 static bool TrimReadRequest(long long &offs, long &len, long rasize, long blksize); 00043 00044 XrdClient_RAStrategy GetCurrentStrategy() { return currstrategy; } 00045 }; 00046 00047 00048 00049 00050 00051 00052 00053 00054 #endif
1.5.1