For #1, when all store files are selected for compaction, the compaction becomes major
see 'Determine the Optimal Number of Pre-Split Regions' under: http://hbase.apache.org/book.html#disable.splitting See also http://hbase.apache.org/book.html#managed.compactions Cheers On Tue, Jan 5, 2016 at 6:52 AM, Mehdi Ben Haj Abbes <[email protected]> wrote: > Hi folks, > > I'm using hbase 0.98. I have heavy writes workload. I'm writing to one > table with one CF compressed with GZ. My table is pre splitted to 27 > regions. As I start writing to this table I start seeing HFiles of the size > of 2-4 MB across the regions. I have the default hbase configuration for > compaction properties. The compactions start as soon as I start writing to > HBase but many of these compaction are major ones. I can see this through > HBase master UI on the table details view. So I wanted to understand when a > compaction becomes major. > > Another question, If I'm not wrong we have a memstore per region, so when a > memstore is flushed I will have a HFile with 128MB but I only see files > with 42MB (without compression and 2.5MB when compressed with GZ). > > Any explanation ? > > Thanks in advance. > -- > Mehdi BEN HAJ ABBES >
