fTotBytes is incremented during the filling of the Tree in TBranch::Fill. Are you sure that you call TTree::Fill ? Here is the doc of TTree::AutoSave Rene Brun // When large Trees are produced, it is safe to activate the AutoSave // procedure. Some branches may have buffers holding many entries. // AutoSave is automatically called by TTree::Fill when the number of bytes // generated since the previous AutoSave is greater than fAutoSave bytes. // This function may also be invoked by the user, for example every // N entries. // Each AutoSave generates a new key on the file. // Once the key with the tree header has been written, the previous cycle // (if any) is deleted. // // Note that calling TTree::AutoSave too frequently (or similarly calling // TTree::SetAutoSave with a small value) is an expensive operation. // You should make tests for your own application to find a compromize // between speed and the quantity of information you may loose in case of // a job crash. // // In case your program crashes before closing the file holding this tree, // the file will be automatically recovered when you will connect the file // in UPDATE mode. // The Tree will be recovered at the status corresponding to the last AutoSave. Wensheng Deng wrote: > > Hi root experts, > > I am learning to use the autosave feature of TTree. > I call SetAutoSave() right after I create a tree > with statements like: > kinkTree = new TTree("kinkAnalysis","STAR kink analysis"); > kinkTree->SetAutoSave(1000); // I use 1000 for testing purpose > > But it seems to me that it never autosaves. > > Then I looked into the code TTree.h and TREE_Tree.cxx. > Do 'grep -n fTotBytes' to TREE_Tree.cxx and TTree.h, > it looks like the member variable 'fTotBytes' never get increased. > > Maybe I am wrong somewhere? > > Thanks, > Wensheng
This archive was generated by hypermail 2b29 : Tue Jan 02 2001 - 11:50:22 MET