Do you have a key "a/b" then? What columns does it have? On Wed, Oct 27, 2010 at 9:14 AM, Daniel Doubleday <daniel.double...@gmx.net> wrote: > Hm - > > not sure if I understand the random question. We are using RP. But I wouldn't > know why that should matter. > I thought that the bloom filter hash function should evenly distribute no > matter what keys come in. > > Keys are '/' separated strings (aka paths :-)) > > I do bulk inserts like: (1000 rows at a time, with ~ 50 cols each) > > [ > {'a/b/foo': cols}, > {'a/b/bar': cols}, > {'a/b/baz': cols} > ] > > and before that I would query for 'a/b'. Recursively as in mkdir -p > > If parent paths are missing they would be inserted with the bulk insert. > > The value for BloomFilterFalseRatio has been in the range of 0.19 - 0.59 in > the last couple of hours. Mostly around 0.3 > > We're on 0.6.6 btw > > > On Oct 27, 2010, at 3:58 PM, Jonathan Ellis wrote: > >> This is not expected, no. How random are your queries? If you have a >> couple outlier rows causing the false positives that are being queried >> over and over then that could just be the luck of the draw. >> >> On Wed, Oct 27, 2010 at 5:24 AM, Daniel Doubleday >> <daniel.double...@gmx.net> wrote: >>> Hi people >>> >>> We are currently moving our second use case from mysql to cassandra. While >>> importing the data (ongoing) I noticed that the BloomFilterFalseRation >>> seems to be pretty high compared to another CF which is in used in >>> production right now. >>> >>> Its a hierarchical data model and I cannot avoid to do a read before >>> inserting multiple columns. >>> >>> I see a false positive ration of 0.28 while in my other CF it is 0.00025. >>> >>> The CF has 5 live sstables whiel I read that ratio. At that time I inserted >>> ~ 200k rows with a total of 1M cols. Row keys are pretty large >>> unfortunately (key.length() ~ 60) >>> >>> Just wanted to check if this value is to be expected. >>> >>> >>> >>> Thanks, >>> Daniel >> >> >> >> -- >> Jonathan Ellis >> Project Chair, Apache Cassandra >> co-founder of Riptano, the source for professional Cassandra support >> http://riptano.com > >
-- Jonathan Ellis Project Chair, Apache Cassandra co-founder of Riptano, the source for professional Cassandra support http://riptano.com