Check out o.a.a.server.util.LocalityCheck -Eric
On Wed, Dec 12, 2012 at 1:17 PM, John Vines <[email protected]> wrote: > When a file gets written to hdfs, there is a guarantee the file is local > as long as that systems disks are not full. Accumulo does not have a > locality guarantee as tablets will migrate on occasion. However, as data is > added, major compactions will occur which will restore locality. > On Dec 12, 2012 1:09 PM, "ameet kini" <[email protected]> wrote: > >> >> Along these lines.... >> >> Can someone help me understand how tablets map to files on disk in HDFS? >> From what I understand, after a compaction, there may be one (or more?) >> files on HDFS for a given tablet. Each file can consist of multiple HDFS >> blocks. Does Accumulo guarantee that the tablet serving a given data range >> finds all its blocks locally? If so, how does it keep this guarantee? >> Wouldn't HDFS distribute these blocks around based on HDFS balancing >> strategy? >> >> Thanks, >> Ameet >> >> On Tue, Dec 11, 2012 at 9:37 AM, William Slacum < >> [email protected]> wrote: >> >>> Tablets will split automatically, down to the granularity of a row. >>> >>> >>> On Tue, Dec 11, 2012 at 9:32 AM, Mathias Herberts < >>> [email protected]> wrote: >>> >>>> Hi, >>>> >>>> I've read the user manual for v1.4.2 and I have not seen any mention of >>>> automatic tablet splitting. Is there such a thing in Accumulo or is >>>> pre-splitting the only way to split a table? >>>> >>>> Thanks, >>>> >>>> Mathias. >>>> >>> >>> >>
