Hi Jeff, All of the FSNamesystem methods call logSync() before returning to the client. So, if the edit is lost, it also will not have returned a success to the client.
-Todd On Thu, Jun 10, 2010 at 6:29 PM, Jeff Zhang <zjf...@gmail.com> wrote: > Hi all, > > I check the source code of EditLogFileOutputStream, it seems hadoop > will first write edit log to buffer, then flush to disk. I know that > it will improve performance, but in the other hand it will cause the > edit log in buffer lost when the name node is down. So I wonder is it > possible and necessary to let users do configuration in the conf file > to decide whether use buffer or not? Thanks. > > > > -- > Best Regards > > Jeff Zhang > -- Todd Lipcon Software Engineer, Cloudera
