We need to fix that entry in the book. It is simply not true. It refers to binary compatibility (i.e. using the same Java code with newer versions of the HBase jars), which is not an issue for rolling restarts because all jars are replaced (unless you actually use coprocessors that reach deeply into HBase).
As far as I know there is no issue performing a rolling restart between 0.92 and 0.94. -- Lars ________________________________ From: Andrew Purtell <[email protected]> To: "[email protected]" <[email protected]> Sent: Thursday, January 2, 2014 9:47 AM Subject: Re: Performance between HBaseClient scan and HFileReaderV2 On Thu, Jan 2, 2014 at 9:18 AM, Jerry Lam <[email protected]> wrote: > I would like to switch to 0.94 but we are using 0.92.1 and we will not > change until the end of 2014. > There are more major performance improvements between 0.92.1 and 0.94.16.1 releases than I can count on two hands. I think the help we can provide you since you cannot change software versions the entire year will be quite limited. 0.94 is a drop-in replacement for 0.92. While you cannot do a rolling upgrade (see http://hbase.apache.org/upgrading.html#upgrade0.94), there won't be a data migration step. I'd suggest trying an upgrade from 0.92.1 to 0.94.16.1 in a dev environment to see if it's at all an option for you. I think we would all recommend this course of action. -- Best regards, - Andy Problems worthy of attack prove their worth by hitting back. - Piet Hein (via Tom White)
