-Is it safe enough to write edit log in buffer before writing to disk ?
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.