Hi Vinayak,

Yes, it should be possible to improve on the 3% CPU usage.

The newTransaction() should be added to line 39 (GraphTraversalSource g = graph.traversal();) as the global g from line 121 is not used.

Marc

Hi Vinayak,

What storage backend do you use? Do I understand right that the storage backend and the load script all run on the same server? If, so, are all available CPU resources actively used during batch loading? What is CPU usage of the groovy process and what of the storage backend?

Specific details in the script:

• did you specify storage.batch-loading=true

• I am not sure whether each traversal() call on the graph gets its own thread-independent transaction (that is why ask for the groovy CPU usage). Maybe you need g = graph.newTransaction().traversal() in CsvImporter
• I assume that the global GraphTraversalSource g at the bottom of the script is not used for the bulk loading.

Best wishes,    Marc

Is it expected that tx.log-tx works only for fresh JanusGraph setup?

No. It should work well for your existing JanusGraph setup too. Note that it is a GLOBAL option so it must be changed for the entire cluster. See https://docs.janusgraph.org/basics/configuration/#global-configuration

Best,
Boxuan

Hi All,

I am trying to enable write-ahead logs by using the config property: tx.log-tx to handle transaction recovery.
It's working fine for new JanusGraph setup but not working for Janusgraph setup which already used for some time.

Is it expected that tx.log-tx works only for fresh JanusGraph setup?
Do we need to follow any additional steps to enable tx.log-tx for existing Janusgraph setup.

Thanks,
Radhika

Hi Jigar,

Yes, I think it is an issue. I did not fully dive into it, in particular I did not check whether any tests exist for the "disable schema check" configuration option. So, go ahead and create an issue for it.

Best wishes,   Marc

Hi Marc

Here is the full stack trace,

https://gist.github.com/jigs1993/5cc1682a919cfb5e8290bf4636f1c766

possible fix is here: https://github.com/jigs1993/janusgraph/pull/1/files

Let me know if you think this is actually an issue, i can raise the PR against the master branch

Hi Jigar,

Can you provide the properties file you used for opening the graph, as well as the complete stacktrace for the exception listed above?

Best wishes,    Marc

org.apache.hadoop.hbase.security.AccessDeniedException: org.apache.hadoop.hbase.security.AccessDeniedException: Insufficient permissions (user=<user>, scope=<namespace>:<table>, params=[table=<namespace>:<table>],action=CREATE)
	at org.apache.hadoop.hbase.security.access.AccessController.requirePermission(AccessController.java:468)
	at org.apache.hadoop.hbase.security.access.AccessController.preGetTableDescriptors(AccessController.java:2576)

got above error while OLAP without create permission to <user> at line https://github.com/JanusGraph/janusgraph/blob/master/janusgraph-hbase/src/main/java/org/janusgraph/diskstorage/hbase/HBaseStoreManager.java#L732

it succeeded with CREATE permission given to user

looks like it is due to this call https://github.com/JanusGraph/janusgraph/blob/master/janusgraph-hbase/src/main/java/org/janusgraph/diskstorage/hbase/HBaseStoreManager.java#L543 being made regardless of the boolean variable skipSchemaCheck value https://github.com/JanusGraph/janusgraph/blob/master/janusgraph-hbase/src/main/java/org/janusgraph/diskstorage/hbase/HBaseStoreManager.java#L258

is this a bug? 

Hi Laura,

Thanks for explaining in more detail. Another example is a "color" property. Different data sources could use different types of color objects. As long as you do not want to query for paints and socks with the same color, there is no real need to harmonize the color data-value types.
Also note that an index on a property can already be constrained to a single vertex or edge label. So, if anyone would contribute your idea as a JanusGraph feature, I would guess there would be no objection.

Best wishes,   Marc

Janus describes itself like this

a scalable graph database optimized for storing and querying graphs containing hundreds of billions of vertices and edges distributed across a multi-machine cluster

but my feeling when using it is that this definition means "a simple schema with billions of vertices/edges" and not "a graph with a large schema". This limitation with properties is an example. What I mean is a graph big enough that vertices on one corner of the graph represent something entirely different (semantically) from vertices on the far end of the same graph. So for example, I could use property "age" with a meaning, but use it with a completely different meaning somewhere else on the graph. Because properties names are unique, I must namespace them, for example "contextA.age" and "contextB.Age". But if nodes could be grouped by "context" for example, or maybe properties could be bound to labels, I would not need to namespace them and their datatype would only depend by their context.
I don't know if this makes sense to others, but to me it does.
 
 
 

Sent: Tuesday, July 27, 2021 at 2:00 PM
From: hadoopmarc@...
To: janusgraph-users@...
Subject: Re: [janusgraph-users] Property keys unique per label
Hi Laura,

Indeed, unique property key names are a limitation. But to be honest: if two properties have a different data-value type I would say these are different properties, so why give them the same name?

Best wishes,    Marc

Hi Laura,

Indeed, unique property key names are a limitation. But to be honest: if two properties have a different data-value type I would say these are different properties, so why give them the same name?

Best wishes,    Marc

Hi Jonathan,

User authorization for Gremlin Server was introduced in TinkerPop 3.5.0, see https://tinkerpop.apache.org/docs/current/reference/#authorization

JanusGraph will use TinkerPop 3.5.x in its upcoming 0.6.0 release. If you want, you can already build the 0.6.0-SNAPSHOT distribution archives from master, using:

mvn clean install -Pjanusgraph-release -Dgpg.skip=true -DskipTests=true

Best wishes,     Marc

Dear,

I have not found into the documentation on the process to create and manage user and roles in order to contro datal access.
At this page https://docs.janusgraph.org/basics/server/ we can see they are a connection andauthentification through HTTPor websocket.
But I do not see where it is describe how to How to manage users and roles .

Thanks

The documentation says "Property key names must be unique in the graph". Does it mean that it's not possible to have property keys that are unique *per label*? In other words, can I have two distinct properties with the same name but different data-value types, as long as they are applied to vertexes with different labels?

Hi Jonathan,

One thing is not yet clear to me: does your graph fit into a single node (regarding memory and GPU) or do you plan to use distributed pytorch? Either way, I guess it would be most efficient to use a two step process:

1. get all data from janusgraph and store it on disk in a suitable format
2. run pytorch geometric (may be in a distributed way) from the files on disk

JanusGraph only supports the hadoop InputFormats to retrieve graph data in a distributed way. Some teams succeeded in retrieving data from partitions from the janusgraph storage backends (not using any janusgraph API, see here), which could be done in a custom pytorch loader, but this is not documented (yet).

Cool that you apply janusgraph to this use case, so do not hesitate to ask for more details!

Marc

Hi Laura,

Without checking this in the code, it only seems logical that the graph id is ignored, because you have to supply the io readers with an existing Graph instance. Apparently it was chosen to make the user responsible for supplying the Graph that corresponds to the graph id in the xml file.

Marc

The JanusGraph Technical Steering Committee is excited to announce that JanusGraph is now accepting donations.

As you may know, most of JanusGraph contributors are not full-time JanusGraph employees, thus we came up with the idea to try to collect donations from the community to be able to hire full time employees to JanusGraph.

With your help JanusGraph will be able to produce releases much more often and we will be able to develop JanusGraph much faster.

JanusGraph Technical Steering Committee guarantees to be fully transparent with the community about any penny spent. We are accepting contributions via LFX Crowdfunding which has an open ledger where you can check all the transactions made and their descriptions.

LFX Crowdfunding link where JanusGraph accepts donations is : https://crowdfunding.lfx.linuxfoundation.org/projects/janusgraph

Best regards,

Oleksandr Porunov

on behalf of JanusGraph TSC