Hazelcast IMap-并发更新到相同的键，但值不同 [英] Hazelcast IMap - Concurrent updates to the same key, different value

问题描述

未经测试，因为我被困在火车上，电池没电了...

Without testing, because I'm stuck on a train and running out of battery...

我需要确定Hazelcast的IMap并发更新是否是线程安全的，以更新同一密钥但该密钥的值不同.

I need to determine whether or not Hazelcast's IMap concurrent updates are thread safe updating the same key but different values of that key.

例如:

假设我有2个不同的线程更新同一个IMap密钥...

Let's say I have 2 different threads updating the same IMap key...

出于所有意图和目的，此地图如下图所示:

For all intents and purposes, this map looks like the following:

  key: {value1: 1, value2: 2}

一个线程说，

  "I am updating value1 to 3"

另一个线程说(同时)

  "I am updating value2 to 4".

Hazelcast如何处理呢?

How does Hazelcast handle this?

最终结果将如下所示吗?

Will the final result look like the following?

  key: {value1: 3, value2: 4}

推荐答案

Hazelcast使用分区.密钥被散列以找到该条目的正确分区.

Hazelcast uses partitions. Key is hashed to find the right partition for that entry.

每个分区都是单线程的，只有一个分区线程处理每个分区.因此，单个键的两次更新由单个分区线程处理.

Each partition is single-threaded, there is only one partition-thread handling each partition. So two update for a single key are handled by a single partition-thread.

如果两个更新的密钥都位于同一分区中，则这些操作将在单个分区线程上顺序执行.如果每个密钥都位于不同的分区中，则每个更新将由不同的线程处理.

If both updated keys land in the same partition, these operations will be sequential on a single partition-thread. If each key lands in a different partition - different threads will handle each update.

我不太了解您的表示法:key: {value1: 1, value2: 2}->它看起来像一个嵌套的地图.

I don't really understand your notation: key: {value1: 1, value2: 2} -> it looks like a nested map.

您也说:the same key but different values of that key.->在映射中，每个键只有一个值(除非该值是集合或映射)

Also you say: the same key but different values of that key. -> in a map, each key has a single value only (unless the value is a collection or a map)

这篇关于Hazelcast IMap-并发更新到相同的键，但值不同的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！