Neo4j DB-客户端连接

Question

I've got a question about getting control of query 'timeout'. What i want to achive is that i could control 'query timeout' - i want to set it let's say for 3 seconds and if query will take longer, i'll get an exception/whatever.

So far i was trying countless ways, even with overriding some api's to get to the Client within RestRequest to set it there... but i had no transaction controll.

I'm not posting any versions of components i've used/tried already, becouse it's not a big deal to change it. The only 1 restriction is java version 6.

Please, post some advices / approaches that i could use... becouse im out of ideas.

Cheers!

Answer 1

You can configure the transaction timeout in conf/neo4j-server.properties with this setting:

org.neo4j.server.transaction.timeout=NUMBER_OF_SECONDS_HERE

More info available in the docs here

Edit

You can control timeout on a per query basis by enabling execution guard on the Neo4j server and adding a max-execution-time header to your request:

In conf/neo4j-server.properties set:

org.neo4j.server.webserver.limit.executiontime=MAX_POSSIBLE_MS_HERE

In conf/neo4j.properties set:

execution_guard_enabled=true

Then add header max-execution-time=100 and the timeout for that query only will be 100ms.

More information available here and here

I just tested this against both the legacy Cypher HTTP endpoint and the transactional Cypher endpoint for Neo4j 2.2.5.

Answer 2

From what I tested (neo4j 2.2.2) it seems that you will need to set both of the following:

in ./conf/neo4j.properties :

execution_guard_enabled=true

and in ./conf/neo4j-server.properties :

org.neo4j.server.webserver.limit.executiontime={timeout_in_seconds}

(note: this number is in seconds, not milliseconds)

before a query specific timeout, added to the header of the request, will work.

`max-execution-time={timeout_in_milliseconds}`

Neo4j will use whichever timeout is shorter, so specify a large timeout in the property file.