https://github.com/itcraft-cn/frogspawn
a java object pool, for high concurrency and low latency
https://github.com/itcraft-cn/frogspawn
gc-friendry java java-8 low-latency
Last synced: 2 months ago
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a java object pool, for high concurrency and low latency
- Host: GitHub
- URL: https://github.com/itcraft-cn/frogspawn
- Owner: itcraft-cn
- License: apache-2.0
- Created: 2025-03-14T00:53:30.000Z (3 months ago)
- Default Branch: main
- Last Pushed: 2025-03-16T15:09:22.000Z (3 months ago)
- Last Synced: 2025-03-16T16:24:15.128Z (3 months ago)
- Topics: gc-friendry, java, java-8, low-latency
- Language: Java
- Homepage: https://itcraft.cn/frogspawn/
- Size: 88.9 KB
- Stars: 0
- Watchers: 0
- Forks: 0
- Open Issues: 2
-
Metadata Files:
- Readme: README.md
- Changelog: ChangeLog.md
- License: LICENSE
Awesome Lists containing this project
README
# `frogspawn` 蛙卵
**期望**：
> 如青蛙产卵一般，密集产出大量卵，供后续使用
**目标**：
> 作为内存对象池，预分配预处理
**使用场景**
> 低延迟场合下，用以代替分配大量无状态小对象。防止GC导致的延迟波动。
比如：接口序列化/反序列化时
[SerializeCompareSample](src/test/java/cn/itcraft/frogspawn/sample/serial/SerializeCompareSample.java)
## 使用方法
受管理对象需实现一个特定接口 `Resettable`
```java
public class DemoPojo implements Resettable {
...
}
```
需要实现一个创建器
```java
public class DemoPojoCreator implements ObjectCreator {
@Override
public DemoPojo create() {
return new DemoPojo();
}
}
```
构建对象池
```java
PoolStrategy strategy = new PoolStrategy(
FetchStrategy.MUST_FETCH_IN_POOL, FetchFailStrategy.CALL_CREATOR, true);
ObjectsMemoryPool pool =
ObjectsMemoryPoolFactory.newPool(new DemoPojoCreator(), SIZE, strategy);
```
使用
```java
try{
DemoPojo pojo = pojoPool.fetch();
// TODO using pojo
...
}finally{
pojoPool.release(pojo);
}
```
## 三种可选模式
目前支持三种不同模式：
1. 必定从池中取
```java
PoolStrategy strategy = new PoolStrategy(
FetchStrategy.MUST_FETCH_IN_POOL, FetchFailStrategy.CALL_CREATOR, true);
ObjectsMemoryPool pool =
ObjectsMemoryPoolFactory.newPool(new DemoPojoCreator(), SIZE, strategy);
```
1. 取一定次数后返空
```java
PoolStrategy strategy = new PoolStrategy(
FetchStrategy.FETCH_FAIL_AS_NULL, FetchFailStrategy.CALL_CREATOR, true);
ObjectsMemoryPool pojoPool =
ObjectsMemoryPoolFactory.newPool(new DemoPojoCreator(), SIZE, strategy);
```
1. 取一定次数后创建新对象
```java
PoolStrategy strategy = new PoolStrategy(
FetchStrategy.FETCH_FAIL_AS_NEW, FetchFailStrategy.CALL_CREATOR, true);
ObjectsMemoryPool pojoPool =
ObjectsMemoryPoolFactory.newPool(new DemoPojoCreator(), SIZE, strategy);
```
默认方案为最后一种。
## 可选参数
- `-Dfrogspawn.fetch.times`，最大循环取次数，默认值：100
- `-Dfrogspawn.max.capacity`，池最大容量，默认值：67108864，即 65536*1024
- `-Dfrogspawn.cache.capacity`, 线程缓存容量, 默认值: 8，最大值: 64。 设置为 `1` 能获得最大性能。
## 伪共享相关
**以下内容需依赖 `JDK8` 下运行，不能高，不能低!!**
[`@sun.misc.Contended` 源代码](https://github.com/openjdk/jdk/blob/jdk8-b120/jdk/src/share/classes/sun/misc/Contended.java)
里面的注解中说到，对子类可能无效。所以，当前代码中的使用，可能是无效的。
另有文档说，`@Contended` 注解需要 `JVM` 开启参数 `-XX:-RestrictContended` 。
## 更新记录
[ChangeLog](ChangeLog.md)