知识库

在 Neo4j 中计算索引大小的方法。

如果需要出于容量规划目的计算 Neo4j 中索引的大小，则可以使用两种方法。

1) 执行 db.indexes() 过程

CALL db.indexes() YIELD id, name, labelsOrTypes, properties;

从该输出中，您可以获取 id

neo4j@customers> CALL db.indexes() YIELD id, name, labelsOrTypes, properties;
+--------------------------------------------+
| id | name     | labelsOrTypes | properties |
+--------------------------------------------+
| 1  | "kb_idx" | ["Movie"]     | ["idd"]    |
+--------------------------------------------+

1 row available after 49 ms, consumed after another 5 ms

这里的 id 是 1。通过执行没有参数的过程，将返回更完整的列表，包括 state

call db.indexes();
+-------------------------------------------------------------------------------------------------------------------------------------+
| id | name     | state    | populationPercent | uniqueness  | type    | entityType | labelsOrTypes | properties | provider           |
+-------------------------------------------------------------------------------------------------------------------------------------+
| 1  | "kb_idx" | "ONLINE" | 100.0             | "NONUNIQUE" | "BTREE" | "NODE"     | ["Movie"]     | ["idd"]    | "native-btree-1.0" |
+-------------------------------------------------------------------------------------------------------------------------------------+

1 row available after 49 ms, consumed after another 2 ms

现在您有了 id，您可以在 $NEO4J_HOME/data/databases/customers/schema/index 目录中执行 du -h 来获取索引目录。

pwd
/Users/stephenlevett/Documents/scripts/cluster-build-scripts-master/instance1/neo4j-enterprise-4.2.5/data/databases/customers/schema/index/native-btree-1.0

ll
total 0
0 drwxr-xr-x  3 stephenlevett  staff    96B  2 Jun 10:45 1

注意 1 与上面的 id 相匹配。

然后

du -h 1/*
 96K	1/index-1

2) 或者使用 id，您可以在 debug.log 中的数据库名称下的以下部分查找

[customers/eb86f508]   schema:
[customers/eb86f508]     index:
[customers/eb86f508]       native-btree-1.0:
[customers/eb86f508]         1:
[customers/eb86f508]           index-1: 2021-06-02T11:09:20+01:00 - 96.00KiB
[customers/eb86f508]         - Total: 2021-06-02T10:45:09+01:00 - 96.00KiB
[customers/eb86f508]       - Total: 2021-06-02T10:45:08+01:00 - 96.00KiB
[customers/eb86f508]     - Total: 2021-06-02T10:45:08+01:00 - 96.00KiB
[customers/eb86f508]   - Total: 2021-06-02T10:45:08+01:00 - 96.00KiB