转载请注明出处哈:http://carlosfu.iteye.com/blog/2237511
更多BigMemory Go可参考官方文档:
一、BigMemory证书:
(1). 由于BigMemory是商业版,需要从官网上注册、下载证书(目前只支持90天)和对应版本的jar包:
下载地址:http://terracotta.org/downloads/bigmemorygo,完成表单填写,完成下载。
(2). 可以将证书放到classpath下,或者加入启动参数:
-Dcom.tc.productkey.path=/path/to/terracotta-license.key
(3). 证书示例:
其中:
二、依赖
1. BigMemory依赖
<bigmemory.version>4.0.5</bigmemory.version> <ehcache-ee.version>2.7.5</ehcache-ee.version> <dependency> <groupId>org.terracotta.bigmemory</groupId> <artifactId>bigmemory</artifactId> <version>${bigmemory.version}</version> </dependency> <dependency> <groupId>net.sf.ehcache</groupId> <artifactId>ehcache-ee</artifactId> <version>${ehcache-ee.version}</version> </dependency>
2. 序列化工具protostuff依赖
<protostuff.version>1.0.8</protostuff.version> <dependency> <groupId>com.dyuproject.protostuff</groupId> <artifactId>protostuff-runtime</artifactId> <version>${protostuff.version}</version> </dependency> <dependency> <groupId>com.dyuproject.protostuff</groupId> <artifactId>protostuff-core</artifactId> <version>${protostuff.version}</version> </dependency>
3. logback依赖(logback实现了slf4j-api)
<logback.version>1.0.13</logback.version> <dependency> <groupId>ch.qos.logback</groupId> <artifactId>logback-core</artifactId> <version>${logback.version}</version> </dependency> <dependency> <groupId>ch.qos.logback</groupId> <artifactId>logback-classic</artifactId> <version>${logback.version}</version> </dependency>
4. 引入junit
<junit.version>4.11</junit.version> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>${junit.version}</version> </dependency>
5.最终pom配置
<properties> <bigmemory.version>4.0.5</bigmemory.version> <ehcache-ee.version>2.7.5</ehcache-ee.version> <protostuff.version>1.0.8</protostuff.version> <logback.version>1.0.13</logback.version> <junit.version>4.11</junit.version> </properties> <dependencies> <dependency> <groupId>org.terracotta.bigmemory</groupId> <artifactId>bigmemory</artifactId> <version>${bigmemory.version}</version> </dependency> <dependency> <groupId>net.sf.ehcache</groupId> <artifactId>ehcache-ee</artifactId> <version>${ehcache-ee.version}</version> </dependency> <dependency> <groupId>com.dyuproject.protostuff</groupId> <artifactId>protostuff-runtime</artifactId> <version>${protostuff.version}</version> </dependency> <dependency> <groupId>com.dyuproject.protostuff</groupId> <artifactId>protostuff-core</artifactId> <version>${protostuff.version}</version> </dependency> <dependency> <groupId>ch.qos.logback</groupId> <artifactId>logback-core</artifactId> <version>${logback.version}</version> </dependency> <dependency> <groupId>ch.qos.logback</groupId> <artifactId>logback-classic</artifactId> <version>${logback.version}</version> </dependency> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>${junit.version}</version> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>3.1</version> <configuration> <source>1.7</source> <target>1.7</target> <encoding>UTF-8</encoding> </configuration> </plugin> </plugins> </build>
三、BigMemory配置
BigMemory的配置一般也叫ehcache.xml, 放到classpath下:我们使用极简配置
<?xml version="1.0" encoding="UTF-8" ?> <ehcache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="http://ehcache.org/ehcache.xsd"> <cache name="firstOffHeapCache" maxBytesLocalHeap="32M" maxBytesLocalOffHeap="1024M"/> </ehcache>
Bigmemory的配置相对于Ehcache添加了两个属性:
maxBytesLocalOffHeap: 最大堆外内存
maxBytesLocalHeap:堆外内存在堆内内存的热点数据最大值
maxBytesLocalHeap:堆外内存在堆内内存的热点数据最大值
四、logback配置
<?xml version="1.0" encoding="UTF-8"?> <configuration scan="true" scanPeriod="5 seconds"> <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender"> <encoder> <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern> </encoder> </appender> <root level="INFO"> <appender-ref ref="STDOUT"/> </root> </configuration>
五、BigMemory测试:
1. 一个实体类:
package com.sohu.tv.bigmemory.first; import java.util.Date; /** * 俱乐部 * * @author leifu * @Date 2015年7月28日 * @Time 下午1:43:53 */ public class Club { /** * 俱乐部id */ private int id; /** * 俱乐部名 */ private String clubName; /** * 俱乐部描述 */ private String clubInfo; /** * 创建日期 */ private Date createDate; /** * 排名 */ private int rank; public Club(int id, String clubName, String clubInfo, Date createDate, int rank) { super(); this.id = id; this.clubName = clubName; this.clubInfo = clubInfo; this.createDate = createDate; this.rank = rank; } public Club() { super(); } public int getId() { return id; } public void setId(int id) { this.id = id; } public String getClubName() { return clubName; } public void setClubName(String clubName) { this.clubName = clubName; } public String getClubInfo() { return clubInfo; } public void setClubInfo(String clubInfo) { this.clubInfo = clubInfo; } public Date getCreateDate() { return createDate; } public void setCreateDate(Date createDate) { this.createDate = createDate; } public int getRank() { return rank; } public void setRank(int rank) { this.rank = rank; } @Override public String toString() { return "Club [id=" + id + ", clubName=" + clubName + ", clubInfo=" + clubInfo + ", createDate=" + createDate + ", rank=" + rank + "]"; } }
2. BigMemory测试(Ehcache单元测试作为测试)
(1) 单元测试:
package com.sohu.tv.bigmemory.first; import java.util.Date; import org.junit.BeforeClass; import org.junit.Test; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import net.sf.ehcache.Cache; import net.sf.ehcache.CacheManager; import net.sf.ehcache.Element; /** * 第一个BigMemory测试 * * @author leifu * @Date 2015年8月12日 * @Time 上午10:14:13 */ public class FirstBigmemoryTest { private static Logger logger = LoggerFactory.getLogger(FirstBigmemoryTest.class); private static Cache cache; private static final String BIGMEORY_CACHE_NAME = "firstOffHeapCache"; @BeforeClass public static void setUp() { CacheManager cacheManager = CacheManager.create(FirstBigmemoryTest.class.getClassLoader() .getResourceAsStream("ehcache.xml")); // 打印cacheManager管理的cache String[] cacheNameArr = cacheManager.getCacheNames(); for (String cacheName : cacheNameArr) { logger.info("cacheName: {}", cacheName); } cache = cacheManager.getCache(BIGMEORY_CACHE_NAME); } @Test public void testCRUD() { logger.info("At start, bigmemory object size: {}", cache.getSize()); // 唯一key String key = "football:club:1"; Club club = new Club(1, "AC", "AC米兰", new Date(), 1); // 增 Element element = new Element(key, club); cache.put(element); logger.info("after add bigmemory object size: {}", cache.getSize()); // 查 Element elementResult = cache.get(key); Club clubResult = (Club) elementResult.getObjectValue(); logger.info("get key {} value is {}", key, clubResult.toString()); // 修改 club.setRank(8888); cache.put(element); logger.info("after set bigmemory object size: {}", cache.getSize()); // 再查 Element elementResultAgain = cache.get(key); Club clubResultAgain = (Club) elementResultAgain.getObjectValue(); logger.info("get key {} again value is {}", key, clubResultAgain.toString()); // 删 boolean removeResult = cache.remove(key); logger.info("remove result is {}, after remove bigmemory object size: {}", removeResult, cache.getSize()); // 增加一条,观察下次启动 cache.put(element); logger.info("At final, bigmemory object size: " + cache.getSize()); // 生产环境不要使用,影响性能 logger.info("At final, bigmemory memory size: " + cache.calculateInMemorySize()); } }
(2) 输出报错:Club必须序列化
(3) 修复:Club实现序列化接口
public class Club implements Serializable
(4) 输出结果正常:
输出信息包含证书的验证、BigMemory堆外内存的分配
11:04:00.965 [main] INFO o.t.license.ehcache.LicenseManager - Terracotta license loaded from resource /terracotta-license.key
Date of Issue: 2015-08-19
Expiration Date: 2015-11-17
License Type: Trial
License Number: 1009994
Licensee: deren zhang, it
Email: 490431513@qq.com
Product: BigMemory Go
Edition: DX
Capabilities: ehcache, TMC, ehcache offheap
Max Client Count: 0
ehcache.maxOffHeap: 32G
11:04:01.287 [main] INFO n.s.e.p.s.f.AnnotationSizeOfFilter - Using regular expression provided through VM argument net.sf.ehcache.pool.sizeof.ignore.pattern for IgnoreSizeOf annotation : ^.*cache\..*IgnoreSizeOf$
11:04:01.296 [main] INFO n.sf.ehcache.pool.sizeof.AgentLoader - Located valid 'tools.jar' at 'C:\Program Files\Java\jdk1.7.0_60\jre\..\lib\tools.jar'
11:04:01.358 [main] INFO n.s.e.pool.sizeof.JvmInformation - Detected JVM data model settings of: 64-Bit HotSpot JVM with Compressed OOPs
11:04:01.430 [main] INFO n.sf.ehcache.pool.sizeof.AgentLoader - Extracted agent jar to temporary file C:\Users\leifu\AppData\Local\Temp\ehcache-sizeof-agent1571240522467793322.jar
11:04:01.430 [main] INFO n.sf.ehcache.pool.sizeof.AgentLoader - Trying to load agent @ C:\Users\leifu\AppData\Local\Temp\ehcache-sizeof-agent1571240522467793322.jar
11:04:01.438 [main] INFO n.s.e.pool.impl.DefaultSizeOfEngine - using Agent sizeof engine
11:04:01.510 [main] INFO n.s.e.s.offheap.OffHeapStoreFactory - Creating Off-Heap Area Using Config
Heuristic Configuration: firstOffHeapCache
Maximum Size (specified) : 2GB
Minimum Chunk Size : 128MB
Maximum Chunk Size : 1GB
Concurrency : 64
Initial Segment Table Size : 1K slots
Segment Data Page Size : 1MB
11:04:01.515 [main] INFO c.t.o.p.UpfrontAllocatingPageSource - Allocating 2GB in chunks
11:04:02.215 [main] INFO c.t.o.p.UpfrontAllocatingPageSource - Allocated 2GB in 1GB chunks.
11:04:02.215 [main] INFO c.t.o.p.UpfrontAllocatingPageSource - Took 699 ms to create CacheManager off-heap storage of 2GB.
11:04:02.304 [main] INFO c.s.t.b.first.FirstBigmemoryTest - cacheName: firstOffHeapCache
11:04:02.307 [main] INFO c.s.t.b.first.FirstBigmemoryTest - At start, bigmemory object size: 0
11:04:02.343 [main] INFO c.s.t.b.first.FirstBigmemoryTest - after add bigmemory object size: 1
11:04:02.346 [main] INFO c.s.t.b.first.FirstBigmemoryTest - get key football:club:1 value is Club [id=1, clubName=AC, clubInfo=AC米兰, createDate=Sat Aug 22 11:04:02 CST 2015, rank=1]
11:04:02.396 [main] INFO c.s.t.b.first.FirstBigmemoryTest - after set bigmemory object size: 1
11:04:02.396 [main] INFO c.s.t.b.first.FirstBigmemoryTest - get key football:club:1 again value is Club [id=1, clubName=AC, clubInfo=AC米兰, createDate=Sat Aug 22 11:04:02 CST 2015, rank=8888]
11:04:02.397 [main] INFO c.s.t.b.first.FirstBigmemoryTest - remove result is true, after remove bigmemory object size: 0
11:04:02.398 [main] INFO c.s.t.b.first.FirstBigmemoryTest - At final, bigmemory object size: 1
11:04:02.398 [main] INFO c.s.t.b.first.FirstBigmemoryTest - At final, bigmemory memory size: 784
Date of Issue: 2015-08-19
Expiration Date: 2015-11-17
License Type: Trial
License Number: 1009994
Licensee: deren zhang, it
Email: 490431513@qq.com
Product: BigMemory Go
Edition: DX
Capabilities: ehcache, TMC, ehcache offheap
Max Client Count: 0
ehcache.maxOffHeap: 32G
11:04:01.287 [main] INFO n.s.e.p.s.f.AnnotationSizeOfFilter - Using regular expression provided through VM argument net.sf.ehcache.pool.sizeof.ignore.pattern for IgnoreSizeOf annotation : ^.*cache\..*IgnoreSizeOf$
11:04:01.296 [main] INFO n.sf.ehcache.pool.sizeof.AgentLoader - Located valid 'tools.jar' at 'C:\Program Files\Java\jdk1.7.0_60\jre\..\lib\tools.jar'
11:04:01.358 [main] INFO n.s.e.pool.sizeof.JvmInformation - Detected JVM data model settings of: 64-Bit HotSpot JVM with Compressed OOPs
11:04:01.430 [main] INFO n.sf.ehcache.pool.sizeof.AgentLoader - Extracted agent jar to temporary file C:\Users\leifu\AppData\Local\Temp\ehcache-sizeof-agent1571240522467793322.jar
11:04:01.430 [main] INFO n.sf.ehcache.pool.sizeof.AgentLoader - Trying to load agent @ C:\Users\leifu\AppData\Local\Temp\ehcache-sizeof-agent1571240522467793322.jar
11:04:01.438 [main] INFO n.s.e.pool.impl.DefaultSizeOfEngine - using Agent sizeof engine
11:04:01.510 [main] INFO n.s.e.s.offheap.OffHeapStoreFactory - Creating Off-Heap Area Using Config
Heuristic Configuration: firstOffHeapCache
Maximum Size (specified) : 2GB
Minimum Chunk Size : 128MB
Maximum Chunk Size : 1GB
Concurrency : 64
Initial Segment Table Size : 1K slots
Segment Data Page Size : 1MB
11:04:01.515 [main] INFO c.t.o.p.UpfrontAllocatingPageSource - Allocating 2GB in chunks
11:04:02.215 [main] INFO c.t.o.p.UpfrontAllocatingPageSource - Allocated 2GB in 1GB chunks.
11:04:02.215 [main] INFO c.t.o.p.UpfrontAllocatingPageSource - Took 699 ms to create CacheManager off-heap storage of 2GB.
11:04:02.304 [main] INFO c.s.t.b.first.FirstBigmemoryTest - cacheName: firstOffHeapCache
11:04:02.307 [main] INFO c.s.t.b.first.FirstBigmemoryTest - At start, bigmemory object size: 0
11:04:02.343 [main] INFO c.s.t.b.first.FirstBigmemoryTest - after add bigmemory object size: 1
11:04:02.346 [main] INFO c.s.t.b.first.FirstBigmemoryTest - get key football:club:1 value is Club [id=1, clubName=AC, clubInfo=AC米兰, createDate=Sat Aug 22 11:04:02 CST 2015, rank=1]
11:04:02.396 [main] INFO c.s.t.b.first.FirstBigmemoryTest - after set bigmemory object size: 1
11:04:02.396 [main] INFO c.s.t.b.first.FirstBigmemoryTest - get key football:club:1 again value is Club [id=1, clubName=AC, clubInfo=AC米兰, createDate=Sat Aug 22 11:04:02 CST 2015, rank=8888]
11:04:02.397 [main] INFO c.s.t.b.first.FirstBigmemoryTest - remove result is true, after remove bigmemory object size: 0
11:04:02.398 [main] INFO c.s.t.b.first.FirstBigmemoryTest - At final, bigmemory object size: 1
11:04:02.398 [main] INFO c.s.t.b.first.FirstBigmemoryTest - At final, bigmemory memory size: 784
3. BigMemory测试结论:
(1) 堆外内存存储的数据需要序列化。
(2) BigMemory使用Ehcache ee可以自动完成序列化,如果使用BigMemory存储java对象,就会存在SizeOf问题(简单对象除外),所以可以使用预序列化方式序列化要存的数据。
(3) BigMemory启动时候,会寻找BigMemory证书。
11:04:00.965 [main] INFO o.t.license.ehcache.LicenseManager - Terracotta license loaded from resource /terracotta-license.key
(4) 以下是bigMemory启动时打印的DirectMemory分区概述,
Maximum Size (specified) : 2GB
Minimum Chunk Size : 128MB
Maximum Chunk Size : 1GB
Concurrency : 64
Initial Segment Table Size : 1K slots
Segment Data Page Size : 1MB
Minimum Chunk Size : 128MB
Maximum Chunk Size : 1GB
Concurrency : 64
Initial Segment Table Size : 1K slots
Segment Data Page Size : 1MB
根据日志,可以猜测出BigMemory预先将数据空间划分为一系列Chunk,目的为了防止内存碎片化,与Memcache内存分配策略很像.
六、BigMemory堆外内存,JVM启动参数:
-XX:MaxDirectMemorySize=4G
七、BigMemory更多使用示例:
http://www.terracotta.org/documentation/4.0/bigmemorygo/code-samples
八、使用ProtoStuff序列化:
1. ProtoStuff序列化工具:
package com.sohu.tv.serializer; import com.dyuproject.protostuff.LinkedBuffer; import com.dyuproject.protostuff.ProtostuffIOUtil; import com.dyuproject.protostuff.Schema; import com.dyuproject.protostuff.runtime.RuntimeSchema; import java.util.concurrent.ConcurrentHashMap; /** * protostuff序列化工具 * * @author leifu * @Date 2015-8-22 * @Time 上午10:05:20 */ public class ProtostuffSerializer { private static ConcurrentHashMap<Class<?>, Schema<?>> cachedSchema = new ConcurrentHashMap<Class<?>, Schema<?>>(); public <T> byte[] serialize(final T source) { VO<T> vo = new VO<T>(source); final LinkedBuffer buffer = LinkedBuffer.allocate(LinkedBuffer.DEFAULT_BUFFER_SIZE); try { final Schema<VO> schema = getSchema(VO.class); return serializeInternal(vo, schema, buffer); } catch (final Exception e) { throw new IllegalStateException(e.getMessage(), e); } finally { buffer.clear(); } } public <T> T deserialize(final byte[] bytes) { try { Schema<VO> schema = getSchema(VO.class); VO vo = deserializeInternal(bytes, schema.newMessage(), schema); if (vo != null && vo.getValue() != null) { return (T) vo.getValue(); } } catch (final Exception e) { throw new IllegalStateException(e.getMessage(), e); } return null; } private <T> byte[] serializeInternal(final T source, final Schema<T> schema, final LinkedBuffer buffer) { return ProtostuffIOUtil.toByteArray(source, schema, buffer); } private <T> T deserializeInternal(final byte[] bytes, final T result, final Schema<T> schema) { ProtostuffIOUtil.mergeFrom(bytes, result, schema); return result; } private static <T> Schema<T> getSchema(Class<T> clazz) { @SuppressWarnings("unchecked") Schema<T> schema = (Schema<T>) cachedSchema.get(clazz); if (schema == null) { schema = RuntimeSchema.createFrom(clazz); cachedSchema.put(clazz, schema); } return schema; } }
package com.sohu.tv.serializer; import java.io.Serializable; /** * @author leifu * @Date 2015-8-22 * @Time 上午10:05:44 * @param <T> */ public class VO<T> implements Serializable { private T value; public VO(T value) { this.value = value; } public VO() { } public T getValue() { return value; } @Override public String toString() { return "VO{" + "value=" + value + '}'; } }
2. ProtoStuff + BigMemory单元测试:
@Test public void testBigMemoryWithSerializable() { ProtostuffSerializer protostuffSerializer = new ProtostuffSerializer(); // 唯一key String key = "football:club:1"; byte[] clubBytes = protostuffSerializer.serialize(new Club(1, "AC", "AC米兰", new Date(), 1)); // 增 Element element = new Element(key, clubBytes); cache.put(element); // 查 Element elementResult = cache.get(key); byte[] clubBytesResult = (byte[]) elementResult.getObjectValue(); Club clubResult = protostuffSerializer.deserialize(clubBytesResult); logger.info("get key {} value is {}", key, clubResult.toString()); }
输出:
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Capital Bikeshare 数据集是一个包含从2020年5月到2024年8月的自行车共享使用情况的数据集。这个数据集记录了华盛顿特区Capital Bikeshare项目中自行车的租赁模式,包括了骑行的持续时间、开始和结束日期时间、起始和结束站点、使用的自行车编号、用户类型(注册会员或临时用户)等信息。这些数据可以帮助分析和预测自行车共享系统的需求模式,以及了解用户行为和偏好。 数据集的特点包括: 时间范围:覆盖了四年多的时间,提供了长期的数据观察。 细节丰富:包含了每次骑行的详细信息,如日期、时间、天气条件、季节等,有助于深入分析。 用户分类:数据中区分了注册用户和临时用户,可以分析不同用户群体的使用习惯。 天气和季节因素:包含了天气情况和季节信息,可以研究这些因素对骑行需求的影响。 通过分析这个数据集,可以得出关于自行车共享使用模式的多种见解,比如一天中不同时间段的使用高峰、不同天气条件下的使用差异、季节性变化对骑行需求的影响等。这些信息对于城市规划者、交通管理者以及自行车共享服务提供商来说都是非常宝贵的,可以帮助他们优化服务、提高效率和满足用户需求。同时,这个数据集也