Dear Arian, Thanks for your interest in FastBit work. At this time, 64-bit integers are internally handled as doubles in many places! As you have realized already, doubles only give you 48-bit precision while 64-bit integers give you 64-bit precision. Clearly there is a problem. However, this is not an issue that we can fix easily without major rewrite of the software. If it is possible, I suggest that you break 64-bit integers into two 32-bit ones.
From our side, we need to look into redesigning the software to get rid of this issue in a reasonable way.. John PS: Your set of tests might also be revealing some other errors in the current version of FastBit code, I have not had the time to fully explore the issues yet. Thanks. On 3/5/2010 5:31 AM, Arian Bär wrote: > Hi John, > > I am currently evaluating Fastbit 1.1.6 for the use in our research > project in the topic of network monitoring. I encountered a problem a > problem with the processing of unsigned 64-bit integers. It seams that > ibis is not supporting them, if the full value range is used. Here is > a example output where rara can produce a hit and ibis not, given the > same query. It would be very kind if u can help me with that. > > commandline output: > > $ ../ardea -d test -m id:i,foo:ul -r 0,18446744073709551615 > /home/abaer/programs/fastbit-ibis1.1.6/examples/.libs/lt-ardea: verbose level > 0 > Will attempt to parse 1 row > with the following column names and types > id:i,foo:ul > > > $ ../rara test id=0 foo > SELECT foo FROM test WHERE id=0 > --> foo (with counts) > 18446744073709551615, 1 > > $ ../ibis -d test -q "select foo where id=0" > doQuery:: estimate(id=0) took 0 CPU seconds, 0.000777245 elapsed > seconds. The number of hits is 0 > $ ../ibis -d test -q "select foo where id=0" -v > > /home/abaer/programs/fastbit-ibis1.1.6/examples/.libs/lt-ibis: batch > mode, log level 1 > > Completed construction of an ibis::part named test > 1 row and 2 columns > query[9_n8CJiG-mB----0]::setWhereClause -- where "id=0" > query[9_n8CJiG-mB----0]::estimate -- time to compute the bounds: 0 > sec(CPU), 0.000341892 sec(elapsed). > query[9_n8CJiG-mB----0]::estimate -- # of hits for query "id=0" is 0 > doQuery:: estimate(id=0) took 0 CPU seconds, 0.000902891 elapsed > seconds. The number of hits is 0 > /home/abaer/programs/fastbit-ibis1.1.6/examples/.libs/lt-ibis -- total > CPU time 0.01 s, total elapsed time 0.00174713 s > $ ../ibis -d test -q "select foo where id=0" -v2 > > /home/abaer/programs/fastbit-ibis1.1.6/examples/.libs/lt-ibis: batch > mode, log level 1 > > Completed construction of an ibis::part named test > 1 row and 2 columns > query[9_n8CJiG-qJ----0]::setWhereClause -- where "id=0" > query[9_n8CJiG-qJ----0]::estimate -- time to compute the bounds: 0 > sec(CPU), 0.000295162 sec(elapsed). > query[9_n8CJiG-qJ----0]::estimate -- # of hits for query "id=0" is 0 > doQuery:: estimate(id=0) took 0 CPU seconds, 0.000799179 elapsed > seconds. The number of hits is 0 > /home/abaer/programs/fastbit-ibis1.1.6/examples/.libs/lt-ibis -- total > CPU time 0 s, total elapsed time 0.00158167 s > > > It would be very kind if u can help me with this. > > With kind regards, > Arian Bär _______________________________________________ FastBit-users mailing list [email protected] https://hpcrdm.lbl.gov/cgi-bin/mailman/listinfo/fastbit-users
