I've tested it extensively, it's safe to use if your tables aren't splitting like mad eg don't try to do it during a massive import because you forgot to set the memstore size.
J-D On Thu, May 10, 2012 at 9:11 AM, Amandeep Khurana <ama...@gmail.com> wrote: > From what I understand, the online schema update feature (0.92.x onwards) > would allow you to do this without disabling tables. It's experimental in > 0.92. > > On Thu, May 10, 2012 at 9:02 AM, Jeff Whiting <je...@qualtrics.com> wrote: > >> We really need to be able to do this type of thing online. Taking your >> table down just so you can change the compression/bloom/whatever isn't very >> cool for a production cluster. >> >> My $0.02 >> >> ~Jeff >> >> >> On 5/9/2012 10:10 PM, Harsh J wrote: >> >>> Jiajun, >>> >>> Expanding on Jean's guideline (and perhaps the following can be used >>> for the manual as well): >>> >>> 1. Ensure snappy codec works properly, following the test listed on >>> http://hbase.apache.org/book/**snappy.compression.html<http://hbase.apache.org/book/snappy.compression.html>(On >>> all RSes to >>> be sure) >>> >>> 2. Disable the table to prepare for alteration. >>> >>> disable 't' >>>> >>> 2. Change the the CF properties to use Snappy. Use the alter command, >>> for each of the colfams: >>> >>> alter 'table', {NAME=>'f1', COMPRESSION=>'SNAPPY'}, {NAME=>'f2', >>>> COMPRESSION=>'SNAPPY'} … >>>> >>> 3. Re-enable the table. >>> >>> enable 't' >>>> >>> (Make sure to test the table. And do not remove away the old codec >>> immediately. You need to wait until the whole of the table's regions >>> have major compacted, leaving no old-codec-encoded store file traces. >>> Correct me if am wrong there!) >>> >>> On Thu, May 10, 2012 at 7:26 AM, Jiajun Chen<cjjvict...@gmail.com> >>> wrote: >>> >>>> How to convert snappy on existing table .used lzo compression ? >>>> >>>> On 10 May 2012 05:27, Doug >>>> Meil<doug.meil@**explorysmedical.com<doug.m...@explorysmedical.com>> >>>> wrote: >>>> >>>> I'll update the RefGuide with this. This is a good thing for everybody >>>>> to >>>>> know. >>>>> >>>>> >>>>> >>>>> >>>>> >>>>> On 5/9/12 5:08 PM, "Jean-Daniel Cryans"<jdcry...@apache.org> wrote: >>>>> >>>>> Just alter the families, the old store files will get converted during >>>>>> compaction later on. >>>>>> >>>>>> J-D >>>>>> >>>>>> On Wed, May 9, 2012 at 2:06 PM, Otis Gospodnetic >>>>>> <otis_gospodne...@yahoo.com> wrote: >>>>>> >>>>>>> Hi, >>>>>>> >>>>>>> Based on the example on >>>>>>> http://hbase.apache.org/book/**snappy.compression.html<http://hbase.apache.org/book/snappy.compression.html>and >>>>>>> some >>>>>>> search-hadoop.com searches I'm guessing it's not possible to switch >>>>>>> an >>>>>>> existing HBase table to use Snappy. >>>>>>> i.e. a new table with snappy needs to be created and old data imported >>>>>>> into this table. >>>>>>> >>>>>>> Is this correct? >>>>>>> >>>>>>> Thanks, >>>>>>> Otis >>>>>>> ---- >>>>>>> Performance Monitoring for Solr / ElasticSearch / HBase - >>>>>>> http://sematext.com/spm >>>>>>> >>>>>> >>>>> >>>>> >>> >>> >> -- >> Jeff Whiting >> Qualtrics Senior Software Engineer >> je...@qualtrics.com >> >>
