I was in China the past 10 days where I didn't have access to gmail. bq. repeat this sequence a thousand times
You mean proceeding with the next parameter ? bq. use hashing mechanism to transform this long string How is the hash generated ? The hash prefix should presumably evenly distribute the write load. Thanks On Thu, Nov 24, 2016 at 8:13 AM, schausson <schaus...@softera.fr> wrote: > Hi, thanks for your answer. > > About your question related to thread management : yes, I have several > threads (up to 4) that may call my persistence method. > > When I wrote the post, I had not configured anything special about regions > for my table so it basically used default splitting policy I guess. > Next to your answer, I gave a try to this : > /byte[][] splits = new > RegionSplitter.HexStringSplit().split(numberOfRegionServers); > / > Which lead to 12 regions at table creation time. > > It slightly improved performances : persistance drops from 2min to 1min40s > approximately. > > I tried with 24 regions but nothing changed then... > > About how parameters IDs are distributed : to make it simple, I read 5 > values per parameter (*2000) and call persistence, and repeat this sequence > a thousand times. So they should distribute accross all my region servers, > right ? > One additional clue : parameters ID are alphanumeric, evenly distributed > between AAAAA and ZZZZZ, but I add a prefix to them which is long string > (about 25 characters). To save storage space (because rowId is dupplicated > for each cell), I use hashing mechanism to transform this long string into > Long value (and I ahev a mapping table next to the main table), so I dont > really know how these Long values "distribute"... > > Not sure I'm clear... > > > > > > > > > > -- > View this message in context: http://apache-hbase.679495.n3. > nabble.com/Writting-bottleneck-in-HBase-tp4084656p4084678.html > Sent from the HBase User mailing list archive at Nabble.com. >