I think Dhruba did try the approach Joey mentioned. On Mon, Jun 20, 2011 at 8:23 AM, Joey Echeverria <j...@cloudera.com> wrote:
> Is there any reason why the increment has to actually happen on > insert? Couldn't an "increment record" be kept, and then the actual > increment operation be performed lazily, on reads and compactions? > > -Joey > > On Mon, Jun 20, 2011 at 11:14 AM, Andrew Purtell <apurt...@apache.org> > wrote: > >> From: Claudio Martella <claudio.marte...@tis.bz.it> > >> So, basically it's expensive to increment old data. > > > > HBase employs a buffer hierarchy to make updating a working set that can > fit in RAM reasonably efficient. (But like I said there are some things > remaining we can improve in terms of internal data structure management.) > > > > If you are updating a working set that does not fit in RAM or > infrequently such that the value is not maintained in cache, then HBase has > to go to disk and we move from the order of memory access to the order of > disk access. > > > > It will obviously be more expensive to increment old data than newer, but > I'm not sure I understand what you are getting at. Any data management > system with a buffer hierarchy has this behavior. > > > > Compared to what? > > > > - Andy > > > > > > > > -- > Joseph Echeverria > Cloudera, Inc. > 443.305.9434 >
