It seems that when client add entry to one bookie server failed,it will select an extra bookie server and try to add entry to the new one server,then put this relationship to ensembles map in LedgerMetadata. I am worry about that this map will grow up and reach the limit size of zookeeper,because the metadata is stored in zookeeper.Could it happen? Or there is a solution for this situation.
在 2011年11月28日 上午10:25，dennis zhuang <[email protected]>写道： > 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 > > -- 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
