Responding inline John
Sent from my phone, so pardon the typos and brevity. On Aug 9, 2012 9:02 AM, "Hugh Xedni" <[email protected]> wrote: > > Keith, > > From your response... > > "A tablets persistent data is composed of a set of files in HDFS and a set of write ahead logs." > "As long as the other tablet server can read the write ahead logs and HDFS files, no data is lost." > > Question. > I understand when a write arrives at a TabletServer it is written to a Write-Ahead Log and then stored in the MemTable until flusing to HDFS via minor compaction. > 1) Are write ahead logs even used when data is bulk inserted into hdfs then handed to Accumulo? Only for the metadata entries regarding that table and those files. > 2) If not, how is data replication achieved when using bulk insert methods? Hdfs replicates the data, so when the files are created in hdfs they are replicated. > > -- > Thank you, > > Hugh Xedni > > > > On Thu, Jul 26, 2012 at 12:31 PM, David Medinets <[email protected]> wrote: >> >> Thanks, Keith. That explanation is just what I wanted. > > > > >
