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new 653811c [FLINK-21073][docs] Mention that RocksDB would ignore java's
equals/hashCode during comparing objects
653811c is described below
commit 653811c70895f13f04b8c86fbd9b80d0c0c9a69e
Author: Yun Tang <[email protected]>
AuthorDate: Thu Apr 8 22:27:14 2021 +0800
[FLINK-21073][docs] Mention that RocksDB would ignore java's
equals/hashCode during comparing objects
---
docs/content.zh/docs/ops/state/state_backends.md | 2 ++
docs/content/docs/ops/state/state_backends.md | 1 +
2 files changed, 3 insertions(+)
diff --git a/docs/content.zh/docs/ops/state/state_backends.md
b/docs/content.zh/docs/ops/state/state_backends.md
index 66e1b36..e978abf 100644
--- a/docs/content.zh/docs/ops/state/state_backends.md
+++ b/docs/content.zh/docs/ops/state/state_backends.md
@@ -103,6 +103,8 @@ FsStateBackend 适用场景:
*RocksDBStateBackend* 需要配置一个文件系统的 URL
（类型、地址、路径），例如："hdfs://namenode:40010/flink/checkpoints" 或
"file:///data/flink/checkpoints"。
RocksDBStateBackend 将正在运行中的状态数据保存在 [RocksDB](http://rocksdb.org) 数据库中，RocksDB
数据库默认将数据存储在 TaskManager 的数据目录。
+Unlike storing java objects in `HashMapStateBackend`, data is stored as
serialized byte arrays, which are mainly defined by the type serializer,
resulting in key comparisons being byte-wise instead of using Java's
`hashCode()` and `equals()` methods.
+
CheckPoint 时，整个 RocksDB 数据库被 checkpoint 到配置的文件系统目录中。
少量的元数据信息存储到 JobManager 的内存中（高可用模式下，将其存储到 CheckPoint 的元数据文件中）。
diff --git a/docs/content/docs/ops/state/state_backends.md
b/docs/content/docs/ops/state/state_backends.md
index c0f8e63..d121e7e 100644
--- a/docs/content/docs/ops/state/state_backends.md
+++ b/docs/content/docs/ops/state/state_backends.md
@@ -65,6 +65,7 @@ This will ensure that the maximum amount of memory is
allocated for user code on
The EmbeddedRocksDBStateBackend holds in-flight data in a
[RocksDB](http://rocksdb.org) database
that is (per default) stored in the TaskManager local data directories.
+Unlike storing java objects in `HashMapStateBackend`, data is stored as
serialized byte arrays, which are mainly defined by the type serializer,
resulting in key comparisons being byte-wise instead of using Java's
`hashCode()` and `equals()` methods.
The EmbeddedRocksDBStateBackend always performs asynchronous snapshots.
