Thanks for your answer. Another question about bookkeeper is that when a bookie server failed forever(such as disk damage etc.),will bookeeper try to replicate it's entries to other bookie server automically?Or just let it go,then some entries will lose their replications?
在 2011年11月28日 上午10:13，Samuel Guo <[email protected]>写道： > Hello dennis, > > SyncThread only flushed Entry Logs and Index files not journal files. > > Step 4 only happened when entries in journal files are flushed to disk, > which means that when bookkeeper client received responses, the entries are > already persisted in journal files. > > The index may be still in Ledger Cache without being persisted when bookie > server shuts down or crashes. But it is OK. When bookie server restarted, > it can replay entries persisted in journal files to recover index. > > So no entries will be lost when bookkeeper client received their > responses. > > You can read 'Data Management in Bookie Server' section in > doc/bookkeeperOverview.textile for reference. > > Thanks, > Sijie > > 2011/11/28 dennis zhuang <[email protected]> > >> Hi,to add a entry to bookie server,it has four steps as follow: >> >> 1. Append the entry in *Entry Log*, return its position { logId , >> offset } ; >> 2. Update the index of this entry in *Ledger Cache* ; >> 3. Append a transaction of update of this entry in *Journal* ; >> 4. Respond to BookKeeper client ; >> >> And the EntryLogger,Journal and Index files are not forced to device >> right now,but waiting for SyncThread to flush them. >> My question is that bookie server would lost data between data flushs? >> >> >> -- >> 庄晓丹 >> Email: [email protected] >> 伯岩(花名) [email protected] >> Site: http://fnil.net >> >> 淘宝（中国）软件有限公司 / 产品技术部 / Java中间件 >> >> > -- 庄晓丹 Email: [email protected] 伯岩(花名) [email protected] Site: http://fnil.net 淘宝（中国）软件有限公司 / 产品技术部 / Java中间件
