问题
i want to import csv-Files with about 40 million lines into neo4j. For this i try to use the "batchimporter" from https://github.com/jexp/batch-import. Maybe it's a problem that i provide own IDs. This is the example
nodes.csv
i:id l:label
315041100 Person
201215100 Person
315041200 Person
rels.csv :
start end type relart
315041100 201215100 HAS_RELATION 30006
315041200 315041100 HAS_RELATION 30006
the content of batch.properties:
use_memory_mapped_buffers=true
neostore.nodestore.db.mapped_memory=1000M
neostore.relationshipstore.db.mapped_memory=5000M
neostore.propertystore.db.mapped_memory=4G
neostore.propertystore.db.strings.mapped_memory=2000M
neostore.propertystore.db.arrays.mapped_memory=1000M
neostore.propertystore.db.index.keys.mapped_memory=1500M
neostore.propertystore.db.index.mapped_memory=1500M
batch_import.node_index.node_auto_index=exact
./import.sh graph.db nodes.csv rels.csv
will be processed without errors, but it takes about 60 seconds!
Importing 3 Nodes took 0 seconds
Importing 2 Relationships took 0 seconds
Total import time: 54 seconds
When i use smaller IDs - for example 3150411 instead of 315041100 - it takes just 1 second!
Importing 3 Nodes took 0 seconds
Importing 2 Relationships took 0 seconds
Total import time: 1 seconds
Actually i would take even bigger IDs with 10 digits. I don't know what i'm doing wrong. Can anyone see an error?
- JDK 1.7
- batchimporter 2.1.3 (with neo4j 2.1.3)
- OS: ubuntu 14.04
- Hardware: 8-Core-Intel-CPU, 16GB RAM
回答1:
I think the problem is that the batch importer is interpreting those IDs as actual physical ids on disk. And so the time is spent in the file system, inflating the store files up to the size where they can fit those high ids.
The ids that you're giving are intended to be "internal" to the batch import, or? Although I'm not sure how to tell the batch importer that is the case.
@michael-hunger any input there?
回答2:
the problem is that those ID's are internal to Neo4j where they represent disk record-ids. if you provide high values there, Neo4j will create a lot of empty records until it reaches your ids.
So either you create your node-id's starting from 0 and you store your id as normal node property. Or you don't provide node-id's at all and only lookup nodes via their "business-id-value"
i:id id:long l:label
0 315041100 Person
1 201215100 Person
2 315041200 Person
start:id end:id type relart
0 1 HAS_RELATION 30006
2 0 HAS_RELATION 30006
or you have to configure and use an index:
id:long:people l:label
315041100 Person
201215100 Person
315041200 Person
id:long:people id:long:people type relart
0 1 HAS_RELATION 30006
2 0 HAS_RELATION 30006
HTH Michael
Alternatively you can also just write a small java or groovy program to import your data if handling those ids with the batch-importer is too tricky. See: http://jexp.de/blog/2014/10/flexible-neo4j-batch-import-with-groovy/
来源：https://stackoverflow.com/questions/26627394/neo4j-batchimporter-is-slow-with-big-ids