Michael, MultiGet is about performing a set of Get operations in parallel from the client. So it buys you potential performance benefits from the concurrency/distribution of your operations.
Roughly, you would bucket the gets according to their region and regionserver. Then spawn a thread for each RS and fire off the Gets concurrently. If I have 100 Gets to perform on a random set of keys, assuming each get takes 10ms, doing them sequentially will take 1 second. Other factors and RS concurrency aside, with MultiGet on a 10 node cluster, the total time would be reduced to 100ms. With 50 nodes, 20ms. JG > -----Original Message----- > From: Michael Segel [mailto:[email protected]] > Sent: Tuesday, August 24, 2010 7:53 PM > To: [email protected] > Subject: RE: Best way to get multiple non-sequential rows > > > Igor, > > What does this really buy you? > > I'm trying to figure out a use case that would show a benefit from just > fetching the rows individually. Since the rows are not contiguous, the > odds of the next row you want being in cache are going to slight to > most likely not. ;-) > > Can you give a use case where having a 'multi-get' will make life > easier? > > Thx > > -Mike > > > > Date: Wed, 25 Aug 2010 07:17:13 +0600 > > Subject: Re: Best way to get multiple non-sequential rows > > From: [email protected] > > To: [email protected] > > > > Thanks Igor, I will have a look at it. > > > > /Imran > > > > On Tue, Aug 24, 2010 at 10:36 PM, Igor Ranitovic <[email protected]> > wrote: > > > Take a look at > > > https://issues.apache.org/jira/browse/HBASE-1845 > > > > > > As an HBase user, multi gets is something that I have been looking > forward > > > to for some time now. If there is enough interest it would be great > if this > > > becomes part of 0.90. > > > > > > Take care, > > > i. > > > > > > Imran M Yousuf wrote: > > >> > > >> Hi, > > >> > > >> I am using the HBase client API to interact with HBase. I have > noticed > > >> that HTableInterface has operations such as put(List<Put>), > > >> delete(List<Delete>), but there is no similar method for Get. > Using > > >> scan it is possible to load a range of rows, i.e. sequential rows. > My > > >> question is - > > >> how would it be most efficient to load N non-sequential rows? > > >> > > >> Currently I am using get(Get) method N times. > > >> > > > > > > > > > > > > > > -- > > Imran M Yousuf > > Blog: http://imyousuf-tech.blogs.smartitengineering.com/ > > Mobile: +880-1711402557 >
