No. The upcoming HDP 2.2 does have that fix. Cheers
On Thu, Nov 13, 2014 at 5:38 PM, Jianshi Huang <[email protected]> wrote: > Oh, btw, is latest HDP 2.1(0.98.0.2.1.7.0-784-hadoop2) have this fix? > > Jianshi > > On Fri, Nov 14, 2014 at 9:37 AM, Jianshi Huang <[email protected]> > wrote: > > > Thanks Ted. > > > > I think the fix you mentioned is this one HBASE-12078 > > <https://issues.apache.org/jira/browse/HBASE-12078>. > > > > Not sure when our Hadoop admin would upgrade it, ahhh.... > > > > Jianshi > > > > On Thu, Nov 13, 2014 at 11:15 PM, Ted Yu <[email protected]> wrote: > > > >> Keep in mind that Prefix Tree encoding has higher overhead in write path > >> compared to other data block encoding methods. > >> > >> Please use 0.98.7 which has the latest fixes for Prefix Tree encoding. > >> > >> Cheers > >> > >> On Thu, Nov 13, 2014 at 1:27 AM, Jianshi Huang <[email protected] > > > >> wrote: > >> > >> > Thanks Ram, > >> > > >> > How about Prefix Tree based encoding then? HBASE-4676 > >> > <https://issues.apache.org/jira/browse/HBASE-4676> says it's also > >> possible > >> > to do suffix tries? Then it could be a nice fit for JSON String (or > any > >> > long value where changes are small). > >> > > >> > Maybe I should just flatten JSON to columns, hmm...what's the overhead > >> for > >> > a column? > >> > > >> > Jianshi > >> > > >> > On Thu, Nov 13, 2014 at 4:49 PM, ramkrishna vasudevan < > >> > [email protected]> wrote: > >> > > >> > > >>So is it possible to specify FASTDIFF for rowkey/column and DIFF > for > >> > > value > >> > > cell? > >> > > No that is not possible now. All the encoding is per KV only. > >> > > But what you say is definitely worth trying. > >> > > > >> > > >>So would you recommend storing JSON flattened as many columns? > >> > > May be yes. But I have practically not used JSON formats so I may > >> not be > >> > > the best person to comment on this. > >> > > > >> > > Regards > >> > > Ram > >> > > > >> > > On Thu, Nov 13, 2014 at 2:01 PM, Jianshi Huang < > >> [email protected]> > >> > > wrote: > >> > > > >> > > > Thanks Ram, > >> > > > > >> > > > So is it possible to specify FASTDIFF for rowkey/column and DIFF > for > >> > > value > >> > > > cell? > >> > > > > >> > > > So would you recommend storing JSON flattened as many columns? > >> > > > > >> > > > Jianshi > >> > > > > >> > > > On Thu, Nov 13, 2014 at 2:08 PM, ramkrishna vasudevan < > >> > > > [email protected]> wrote: > >> > > > > >> > > > > Hi > >> > > > > > >> > > > > >> Since I'm storing > >> > > > > historical data (snapshot data) and changes between adjacent > value > >> > > cells > >> > > > > are relatively small. > >> > > > > > >> > > > > If the values are changing even if it is smaller the FASTDIFF > will > >> > > > rewrite > >> > > > > the value part. Only if there are exact matches then it would > >> skip > >> > the > >> > > > > value part. JFYI. > >> > > > > > >> > > > > Regards > >> > > > > Ram > >> > > > > > >> > > > > On Thu, Nov 13, 2014 at 11:23 AM, Jianshi Huang < > >> > > [email protected] > >> > > > > > >> > > > > wrote: > >> > > > > > >> > > > > > I thought FASTDIFF was only for rowkey and columns, great if > it > >> > also > >> > > > > works > >> > > > > > in value cell. > >> > > > > > > >> > > > > > And thanks for the bjson link! > >> > > > > > > >> > > > > > Jianshi > >> > > > > > > >> > > > > > On Thu, Nov 13, 2014 at 1:18 PM, Ted Yu <[email protected]> > >> > wrote: > >> > > > > > > >> > > > > > > There is FASTDIFF data block encoding. > >> > > > > > > > >> > > > > > > See also http://bjson.org/ > >> > > > > > > > >> > > > > > > Cheers > >> > > > > > > > >> > > > > > > On Nov 12, 2014, at 9:08 PM, Jianshi Huang < > >> > > [email protected]> > >> > > > > > > wrote: > >> > > > > > > > >> > > > > > > > Hi, > >> > > > > > > > > >> > > > > > > > I'm currently saving JSON in pure String format in the > value > >> > cell > >> > > > and > >> > > > > > > > depends on HBase' block compression to reduce the overhead > >> of > >> > > JSON. > >> > > > > > > > > >> > > > > > > > I'm wondering if there's a more space efficient way to > store > >> > > JSON? > >> > > > > > > > (there're lots of 0s and 1s, JSON String actually is an OK > >> > > format) > >> > > > > > > > > >> > > > > > > > I want to keep the value as a Map since the schema of > source > >> > data > >> > > > > might > >> > > > > > > > change over time. > >> > > > > > > > > >> > > > > > > > Also is there a DIFF based encoding for values? Since I'm > >> > storing > >> > > > > > > > historical data (snapshot data) and changes between > adjacent > >> > > value > >> > > > > > cells > >> > > > > > > > are relatively small. > >> > > > > > > > > >> > > > > > > > > >> > > > > > > > Thanks, > >> > > > > > > > -- > >> > > > > > > > Jianshi Huang > >> > > > > > > > > >> > > > > > > > LinkedIn: jianshi > >> > > > > > > > Twitter: @jshuang > >> > > > > > > > Github & Blog: http://huangjs.github.com/ > >> > > > > > > > >> > > > > > > >> > > > > > > >> > > > > > > >> > > > > > -- > >> > > > > > Jianshi Huang > >> > > > > > > >> > > > > > LinkedIn: jianshi > >> > > > > > Twitter: @jshuang > >> > > > > > Github & Blog: http://huangjs.github.com/ > >> > > > > > > >> > > > > > >> > > > > >> > > > > >> > > > > >> > > > -- > >> > > > Jianshi Huang > >> > > > > >> > > > LinkedIn: jianshi > >> > > > Twitter: @jshuang > >> > > > Github & Blog: http://huangjs.github.com/ > >> > > > > >> > > > >> > > >> > > >> > > >> > -- > >> > Jianshi Huang > >> > > >> > LinkedIn: jianshi > >> > Twitter: @jshuang > >> > Github & Blog: http://huangjs.github.com/ > >> > > >> > > > > > > > > -- > > Jianshi Huang > > > > LinkedIn: jianshi > > Twitter: @jshuang > > Github & Blog: http://huangjs.github.com/ > > > > > > -- > Jianshi Huang > > LinkedIn: jianshi > Twitter: @jshuang > Github & Blog: http://huangjs.github.com/ >
