Thanks Nicolas for the clarification. I had a follow-up query. What will happen if we increased the region size, say from current value of 256 MB to a new value of 2GB? Will existing regions continue to use only 256 MB space?
Is there a way to reorganize the regions so that each regions grows to 2GB size? Thanks, Srikanth -----Original Message----- From: Nicolas Spiegelberg [mailto:nspiegelb...@fb.com] Sent: Tuesday, November 22, 2011 10:59 PM To: user@hbase.apache.org Subject: Re: Region Splits No. The purpose of major compactions is to merge & dedupe within a region boundary. Compactions will not alter region boundaries, except in the case of splits where a compaction is necessary to filter out any Rows from the parent region that are no longer applicable to the daughter region. On 11/22/11 9:04 AM, "Srikanth P. Shreenivas" <srikanth_shreeni...@mindtree.com> wrote: >Will major compactions take care of merging "older" regions or adding >more key/values to them as number of regions grow? > >Regard, >Srikanth > >-----Original Message----- >From: Amandeep Khurana [mailto:ama...@gmail.com] >Sent: Monday, November 21, 2011 7:25 AM >To: user@hbase.apache.org >Subject: Re: Region Splits > >Mark, > >Yes, your understanding is correct. If your keys are sequential >(timestamps >etc), you will always be writing to the end of the table and "older" >regions will not get any writes. This is one of the arguments against >using >sequential keys. > >-ak > >On Sun, Nov 20, 2011 at 11:33 AM, Mark <static.void....@gmail.com> wrote: > >> Say we have a use case that has sequential row keys and we have rows >> 0-100. Let's assume that 100 rows = the split size. Now when there is a >> split it will split at the halfway mark so there will be two regions as >> follows: >> >> Region1 [START-49] >> Region2 [50-END] >> >> So now at this point all inserts will be writing to Region2 only >>correct? >> Now at some point Region2 will need to split and it will look like the >> following before the split: >> >> Region1 [START-49] >> Region2 [50-150] >> >> After the split it will look like: >> >> Region1 [START-49] >> Region2 [50-100] >> Region3 [150-END] >> >> And this pattern will continue correct? My question is when there is a >>use >> case that has sequential keys how would any of the older regions every >> receive anymore writes? It seems like they would always be stuck at >> MaxRegionSize/2. Can someone please confirm or clarify this issue? >> >> Thanks >> >> >> >> >> > >________________________________ > >http://www.mindtree.com/email/disclaimer.html
