Neo4j缓慢创建方法 [英] Neo4j slow creation method

问题描述

在我的Neo4j/Neo4j Spring Data应用程序中，我具有以下实体:

In my Neo4j/Neo4j Spring Data application I have a following entities:

VoteGroup包含与实体Criterion和Decision的关系VOTED_ON和VOTED_FOR以及Vote

VoteGroup contains relationships VOTED_ON and VOTED_FOR to entities Criterion and Decision and list of Vote

@NodeEntity
public class VoteGroup extends BaseEntity {

    private static final String VOTED_ON = "VOTED_ON";
    private final static String VOTED_FOR = "VOTED_FOR";
    private final static String CONTAINS = "CONTAINS";

    @GraphId
    private Long id;

    @RelatedTo(type = VOTED_FOR, direction = Direction.OUTGOING)
    private Decision decision;

    @RelatedTo(type = VOTED_ON, direction = Direction.OUTGOING)
    private Criterion criterion;

    @RelatedTo(type = CONTAINS, direction = Direction.OUTGOING)
    private Set<Vote> votes = new HashSet<>();

    private double avgVotesWeight;

    private long totalVotesCount;

    @Override
    public boolean equals(Object o) {
        if (this == o)
            return true;
        if (o == null || getClass() != o.getClass())
            return false;
        VoteGroup voteGroup = (VoteGroup) o;
        if (id == null)
            return super.equals(o);
        return id.equals(voteGroup.id);
    }

    @Override
    public int hashCode() {
        return id != null ? id.hashCode() : super.hashCode();
    }
.....

}

Vote实体看起来像:

@NodeEntity
public class Vote extends BaseEntity {

    private final static String CONTAINS = "CONTAINS";
    private final static String CREATED_BY = "CREATED_BY";

    @GraphId
    private Long id;

    @RelatedTo(type = CONTAINS, direction = Direction.INCOMING)
    private VoteGroup group;

    @RelatedTo(type = CREATED_BY, direction = Direction.OUTGOING)
    private User author;

    private double weight;

....
}


public class BaseEntity {

    private Date createDate;

    private Date updateDate;

    public BaseEntity() {
    }

    public Date getCreateDate() {
        return createDate;
    }

    public void setCreateDate(Date createDate) {
        this.createDate = createDate;
    }

    public Date getUpdateDate() {
        return updateDate;
    }

    public void setUpdateDate(Date updateDate) {
        this.updateDate = updateDate;
    }

}

也.我使用基于BaseEntity的Neo4j钩子:

also. I use Neo4j hook based on BaseEntity:

@Configuration
@EnableNeo4jRepositories(basePackages = "com.example")
@EnableTransactionManagement
public class Neo4jConfig extends Neo4jConfiguration implements BeanFactoryAware {
    ...

    /**
     * Hook into the application lifecycle and register listeners that perform
     * behaviour across types of entities during this life cycle
     * 
     */
    @Bean
    protected ApplicationListener<BeforeSaveEvent<BaseEntity>> beforeSaveEventApplicationListener() {
        return new ApplicationListener<BeforeSaveEvent<BaseEntity>>() {
            @Override
            public void onApplicationEvent(BeforeSaveEvent<BaseEntity> event) {
                BaseEntity entity = event.getEntity();
                if (entity.getCreateDate() == null) {
                    entity.setCreateDate(new Date());
                } else {
                    entity.setUpdateDate(new Date());
                }
            }
        };
    }

...

}

为了进行投票，我实现了以下方法VoteGroupDaoImpl.createVote:

in order to make a vote, I have implemented following method VoteGroupDaoImpl.createVote:

@Service
@Transactional
public class VoteGroupDaoImpl implements VoteGroupDao {

    @Autowired
    private VoteRepository voteRepository;

    @Autowired
    private VoteGroupRepository voteGroupRepository;

    @Override
    public Vote createVote(Decision decision, Criterion criterion, User author, String description, double weight) {
        VoteGroup voteGroup = getVoteGroupForDecisionOnCriterion(decision.getId(), criterion.getId());
        if (voteGroup == null) {
            voteGroup = new VoteGroup(decision, criterion, weight, 1);
        } else {
            long newTotalVotesCount = voteGroup.getTotalVotesCount() + 1;
            double newAvgVotesWeight = (voteGroup.getAvgVotesWeight() * voteGroup.getTotalVotesCount() + weight) / newTotalVotesCount;
            voteGroup.setAvgVotesWeight(newAvgVotesWeight);
            voteGroup.setTotalVotesCount(newTotalVotesCount);
        }
        voteGroup = voteGroupRepository.save(voteGroup);

        return voteRepository.save(new Vote(voteGroup, author, weight, description));
    }
...

}

和

@Repository
public interface VoteGroupRepository extends GraphRepository<VoteGroup>, RelationshipOperationsRepository<VoteGroup> {

    @Query("MATCH (d:Decision)<-[:VOTED_FOR]-(vg:VoteGroup)-[:VOTED_ON]->(c:Criterion) WHERE id(d) = {decisionId} AND id(c) = {criterionId} RETURN vg")
    VoteGroup getVoteGroupForDecisionOnCriterion(@Param("decisionId") Long decisionId, @Param("criterionId") Long criterionId);

}

现在，方法VoteGroupDaoImpl.createVote的工作速度确实很慢，并且延迟很长..这可能是什么原因?

Right now, method VoteGroupDaoImpl.createVote works really slow with a huge latency .. what can be a reason of that ?

添加的配置文件输出

为

MATCH (d:Decision)<-[:VOTED_FOR]-(vg:VoteGroup)-[:VOTED_ON]->(c:Criterion) WHERE id(d) = {decisionId} AND id(c) = {criterionId} RETURN vg

密码版本:CYPHER 2.2，计划程序:COST.在181毫秒内，数据库共有33次点击.

Cypher version: CYPHER 2.2, planner: COST. 33 total db hits in 181 ms.

配置文件Java代码:

丰富的探查器信息:

带有分析器信息的HTML页面

推荐答案

我已移至新的Neo4j 2.2.4和SDN 3.4.0.RC1，问题消失了

I'm moved to new Neo4j 2.2.4 and SDN 3.4.0.RC1 and the issue disappeared

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