I use SSD on a Debian Server with every sort configuration still at its default value.
Index creation was fast: 524ms. Count is very slow and it doesn't use any index: Planner COST EagerAggregation | +AllNodesScan +------------------+---------------+------------+------------+-------------+-------+ | Operator | EstimatedRows | Rows | DbHits | Identifiers | Other | +------------------+---------------+------------+------------+-------------+-------+ | EagerAggregation | 31623 | 1 | 0 | count(n) | | | AllNodesScan | 1000000000 | 1000000000 | 1000000001 | n | | +------------------+---------------+------------+------------+-------------+-------+ Total database accesses: 1000000001 Il giorno martedì 10 marzo 2015 00:55:04 UTC+1, Michael Hunger ha scritto: > > Can you try to get a thread dump for the connecting? > > Also did you run this on an SSD or HDD? SSD should be much faster! I took > only 40s for me with 12 cores. Maxing out an SSD raid at 1G/s. > > The index will take a while, that's true > > And the cypher statement will pull through 1bn nodes into memory from disk > (so again it is mostly disk speed). > I'd probably use match (n) return count(*) > > Michael > > > On Tuesday, March 10, 2015 at 12:41:12 AM UTC+1, Lorenzo Speranzoni > (@inserpio) wrote: >> >> Hi All, >> >> I'm testing performances on a 1 Billion nodes database. >> >> To create nodes I used Michael Hunger's code here: >> https://gist.github.com/jexp/0ff850ab2ce41c9ca5e6 >> >> The import when really well: it took 5m 22s 235ms >> >> But when I try to connect to the just created database via shell, I took >> really long time. >> That the command I run; >> >> JAVA_OPTS="-Xmx16G -Xms16G -server -d64" ./neo4j-shell -path /path/to/db/ >> I also takes a long time to count the overall nodes, even with an index: >> >> neo4j-sh (?)$ create index on :Person(id); >> >> +-------------------+ >> >> | No data returned. | >> >> +-------------------+ >> >> Indexes added: 1 >> >> 524 ms >> >> >> neo4j-sh (?)$ match (n) return count(n); >> >> +------------+ >> >> | count(n) | >> >> +------------+ >> >> | 1000000000 | >> >> +------------+ >> >> 1 row >> >> 430730 ms >> >> >> Thanks in advance for the help! >> >> Lorenzo >> > -- You received this message because you are subscribed to the Google Groups "Neo4j" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
