Prior to major compaction, region server may need to read HFile(s) written by other region server(s). This could be due to region movement, etc.
Cheers On Fri, Sep 26, 2014 at 11:43 AM, Thomas Kwan <[email protected]> wrote: > Thanks Ted for the pointer. A follow-up question. > > Will the region server always write data to its local hdfs? I am > seeing logs that said the region server is trying to get data from > another data nodes. Under what scenario will a region server needs to > get data from a non-local data node? > > thanks > > > On Fri, Sep 26, 2014 at 7:21 AM, Ted Yu <[email protected]> wrote: > > Region server should be installed on server which is a data node. > > > > Region server count may be lower than data node count. So some data nodes > > would not have region server running. > > > > See http://hbase.apache.org/book.html#regions.arch.locality > > > > Cheers > > > > On Fri, Sep 26, 2014 at 7:02 AM, Thomas Kwan <[email protected]> > wrote: > > > >> Hi there, > >> > >> To get good read performance, should the region server be installed on > >> every data node? (Thinking about data locality here) > >> > >> thanks > >> thomas > >> >
