I tried the bulk load and kv size counts with uncompressed table and it makes sense now. count is equal to store file size. I took a look at the (uncompressed) files and they seem to be OK.
Entire bulk load is ~100GB, when using GZ ends up to be 7GB. Could such a compression ratio make sense in case of many qualifiers per row in a table (avg is 16 but in practice there are some rows with much more and even a small number of rows with hundreds of thousands...) ? If each KeyValue contains the rowkey, and the rowkeys contain more bytes than the qualifiers / values, than the rows repeat themselves in the HFile and actually make most of the HFile, right ? On Wed, Jan 15, 2014 at 9:52 PM, Stack <st...@duboce.net> wrote: > There can be a lot of duplication in what ends up in HFiles but 500MB -> > 32MB does seem too good to be true. > > Could you try writing without GZIP or mess with the hfile reader[1] to see > what your keys look like when at rest in an HFile (and maybe save the > decompressed hfile to compare sizes?) > > St.Ack > 1. http://hbase.apache.org/book.html#hfile > > > On Wed, Jan 15, 2014 at 7:43 AM, Amit Sela <am...@infolinks.com> wrote: > > > I'm talking about the store files size and the ratio between store file > > size and the byte count as counted in PutSortReducer. > > > > > > On Wed, Jan 15, 2014 at 5:35 PM, Ted Yu <yuzhih...@gmail.com> wrote: > > > > > See previous discussion: http://search-hadoop.com/m/85S3A1DgZHP1 > > > > > > > > > On Wed, Jan 15, 2014 at 5:44 AM, Amit Sela <am...@infolinks.com> > wrote: > > > > > > > Hi all, > > > > I'm trying to measure the size (in bytes) of the data I'm about to > load > > > > into HBase. > > > > I'm using bulk load with PutSortReducer. > > > > All bulk load data is loaded into new regions and not added to > existing > > > > ones. > > > > > > > > In order to count the size of all KeyValues in the Put object I > iterate > > > > over the Put's familyMap.values() and sum the KeyValue lengths. > > > > After loading the data, I check the region size by summing the > > > > RegionLoad.getStorefileSizeMB(). > > > > Counting the Put objects size predicted ~500MB per region but in > > > practice I > > > > got ~32MB per region. > > > > the table uses GZ compression but this cannot be the cause of such a > > > > difference. > > > > > > > > Is counting the Put's KeyValues the correct way to count a row size ? > > Is > > > it > > > > comparable to the store files size ? > > > > > > > > Thanks, > > > > Amit. > > > > > > > > > >
