bq. HBase will first check if the data exist in memstore, if not, it will check the disk
For read path, don't forget block cache / bucket cache. Cheers On Wed, Aug 6, 2014 at 7:54 AM, yonghu <[email protected]> wrote: > I did not quite understand your problem. You store your data in HBase, and > I guess later you also will read data from it. Generally, HBase will first > check if the data exist in memstore, if not, it will check the disk. If you > set the memstore to 0, it denotes every read will directly forward to disk. > How heavy will be the I/O cost? Moreover, you can think memstore as a > buffer management in RDBMS. > > > On Tue, Aug 5, 2014 at 5:54 AM, Alex Newman <[email protected]> wrote: > > > Could you explain a bit more of why you don't want a memstore? I can't > see > > why it is harmful. Sorry to be dense. > > On Aug 3, 2014 11:24 AM, "Ozhan Gulen" <[email protected]> wrote: > > > > > Hello, > > > In our hbase cluster memstore flush size is 128 mb. And to insert data > to > > > tables, we only use bulk load tool. Since bulk loading bypasses > > memstores, > > > they are never used, so we want to minimize memstore flush size. But > > > memstore flush size is used in many important calculations in hbase > such > > > that; > > > > > > region split size = Min (R^2 * “hbase.hregion.memstore.flush.size”, > > > “hbase.hregion.max.filesize”) > > > > > > So setting memstore value smaller or "0" for example, results in some > > > other problems. > > > What do you suggest us in that case. Setting memstore size to 128 holds > > > some memory for tens of regions in region server and we want to get rid > > of > > > it. > > > Thanks a lot. > > > > > > ozhan > > > > > >
