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Redis：解決分布式高并發(fā)修改同一個Key的問題

發(fā)布時間：2020-07-04 06:42:10 來源：網(wǎng)絡(luò) 閱讀：3726 作者：wx5d30212829a35 欄目：編程語言

本文是通過watch（監(jiān)控）+mutil（事務(wù)）實現(xiàn)應(yīng)用于在分布式高并發(fā)處理等相關(guān)場景。下邊先通過redis-cli.exe來測試多個線程修改時，遇到問題及解決問題。

高并發(fā)下修改同一個key遇到的問題：

1）定義一個hash類型的key，key為：lock_test，元素locker的值初始化為0。

2）實現(xiàn)高并發(fā)下對locker元素的值遞增：定義64個多線程，并發(fā)的對lock_test元素locker的值進行修改。

package?com.dx.es;
import?java.util.concurrent.CountDownLatch;
import?redis.clients.jedis.Jedis;
import?redis.clients.jedis.JedisPool;
public?class?Test_UnLock?{
?public?static?void?main(String[]?args)?{
?final?JedisPool?pool?=?RedisUtil.getPool();
?//?獲得jedis對象
?Jedis?jedis?=?pool.getResource();
?jedis.hset("lock_test",?"locker",?"0");
?String?val?=?jedis.hget("lock_test",?"locker");
?System.out.println("lock_test.locker的初始值為："?+?val);
?jedis.close();
?int?threahSize?=?64;
?final?CountDownLatch?threadsCountDownLatch?=?new?CountDownLatch(threahSize);
?Runnable?handler?=?new?Runnable()?{
?public?void?run()?{
?Jedis?jedis?=?pool.getResource();
?Integer?integer?=?Integer.valueOf(jedis.hget("lock_test",?"locker"));
?jedis.hset("lock_test",?"locker",?String.valueOf(integer?+?1));
?jedis.close();
?threadsCountDownLatch.countDown();
?}
?};
?for?(int?i?=?0;?i?<?threahSize;?i++)?{
?new?Thread(handler).start();
?}
?//?等待所有并行子線程任務(wù)完成。
?try?{
?threadsCountDownLatch.await();
?}?catch?(InterruptedException?e)?{
?e.printStackTrace();
?}
?System.out.println("complete");
?val?=?jedis.hget("lock_test",?"locker");
?System.out.println(val);
?}
}

RedisUtil.java

package?com.dx.es;
import?redis.clients.jedis.JedisPool;
import?redis.clients.jedis.JedisPoolConfig;
public?class?RedisUtil?{
?public?static?JedisPool?getPool()?{
?//?簡單創(chuàng)建?Jedis的方法：
?//?final?Jedis?jedis?=?new?Jedis("127.0.0.1",6379);
?//?下邊使用線程池的方案：jedis對象是線程不安全的，因此在并發(fā)情況下要使用JedisPool,默認情況下jedisPool只支持8個連接，因此在聲明JedisPool時要先修改JedisPool的最大連接數(shù)
?JedisPoolConfig?config?=?new?JedisPoolConfig();
?//?修改最大連接數(shù)
?config.setMaxTotal(32);
?
?//?聲明一個線程池
?JedisPool?pool?=?new?JedisPool(config,?"127.0.0.1",?6379);
?return?pool;
?}
}

此時，會出現(xiàn)以下問題：

  1. A線程獲取key的值為0，而B線程也獲取jkey的值0，則A把key值遞增為1，B線程也實現(xiàn)把key值遞增為1。兩個線程都執(zhí)行了key值修改：0到1。

  2. 在1）中最終key修改為了1，但是c線程獲取key的值為0（因為c線程讀取key值時，a、b線程還未觸發(fā)修改，因此c線程讀取到的值為0），此時d線程讀取到的值為1（因為d線程讀取key值時，a、b線程已觸發(fā)修改，一次d線程取到的值為1）。

  3. 此時假設(shè)d線程優(yōu)先觸發(fā)遞增，則在c線程未觸發(fā)提交之前d線程已經(jīng)把值修改了2，但是c此時并不知道在它獲取到值到修改之前這段時間發(fā)生了什么，直接把值修改1。

此時執(zhí)行打印結(jié)果為：

lock_test.locker的初始值為：0
complete
24?#備注：也可能是其他值，可能是正確值64的可能性比較小。

通過watch+mutil解決并發(fā)修改的問題：

需要掌握Redis 事務(wù)命令：

Redis：解決分布式高并發(fā)修改同一個Key的問題


Redis 事務(wù)可以一次執(zhí)行多個命令， 并且?guī)в幸韵聝蓚€重要的保證：

  • 批量操作在發(fā)送 EXEC 命令前被放入隊列緩存。

  • 收到 EXEC 命令后進入事務(wù)執(zhí)行，事務(wù)中任意命令執(zhí)行失敗，其余的命令依然被執(zhí)行。

  • 在事務(wù)執(zhí)行過程，其他客戶端提交的命令請求不會插入到事務(wù)執(zhí)行命令序列中。

一個事務(wù)從開始到執(zhí)行會經(jīng)歷以下三個階段：

  • 開始事務(wù)。

  • 命令入隊。

  • 執(zhí)行事務(wù)。

備注：概念性摘自《http://www.runoob.com/redis/redis-transactions.html》

redis-cli.exe下的事務(wù)操作：

#?事務(wù)被成功執(zhí)行
redis?127.0.0.1:6379>?MULTI
OK
redis?127.0.0.1:6379>?INCR?user_id
QUEUED
redis?127.0.0.1:6379>?INCR?user_id
QUEUED
redis?127.0.0.1:6379>?INCR?user_id
QUEUED
redis?127.0.0.1:6379>?PING
QUEUED
redis?127.0.0.1:6379>?EXEC
1)?(integer)?1
2)?(integer)?2
3)?(integer)?3
4)?PONG

并發(fā)情況下使用watch+mutil操作：

事務(wù)塊內(nèi)所有命令的返回值，按命令執(zhí)行的先后順序排列。 當操作被打斷時，返回空值 nil 。

A線程：

#?監(jiān)視?key?，且事務(wù)成功執(zhí)行
redis?127.0.0.1:6379>?WATCH?lock?lock_times
OK
redis?127.0.0.1:6379>?MULTI
OK
redis?127.0.0.1:6379>?SET?lock?"huangz"
QUEUED
redis?127.0.0.1:6379>?INCR?lock_times
QUEUED
redis?127.0.0.1:6379>?EXEC
1)?OK
2)?(integer)?1

B線程：

#?監(jiān)視?key?，且事務(wù)被打斷
redis?127.0.0.1:6379>?WATCH?lock?lock_times
OK
redis?127.0.0.1:6379>?MULTI
OK
redis?127.0.0.1:6379>?SET?lock?"joe"?#?就在這時，另一個客戶端修改了?lock_times?的值
QUEUED
redis?127.0.0.1:6379>?INCR?lock_times
QUEUED
redis?127.0.0.1:6379>?EXEC?#?因為?lock_times?被修改，?joe?的事務(wù)執(zhí)行失敗
(nil)

上邊演示了A、B線程并發(fā)下的watch+mutil操作情況。

解決高并發(fā)下修改同一個key遇到的問題：

package?com.dx.es;
import?java.util.List;
import?java.util.concurrent.CountDownLatch;
import?redis.clients.jedis.Jedis;
import?redis.clients.jedis.JedisPool;
import?redis.clients.jedis.Transaction;
public?class?Test_Lock3?{
?public?static?void?main(String[]?args)?{
?final?JedisPool?pool?=?RedisUtil.getPool();
?//?對測試key賦初始值
?Jedis?jedis?=?pool.getResource();
?jedis.hset("lock_test",?"locker",?"0");
?String?val?=?jedis.hget("lock_test",?"locker");
?System.out.println("lock_test.locker的初始值為："?+?val);
?jedis.close();
?int?threahSize?=?64;
?final?CountDownLatch?threadsCountDownLatch?=?new?CountDownLatch(threahSize);
?Runnable?handler?=?new?Runnable()?{
?public?void?run()?{
?Jedis?jedis?=?pool.getResource();
?while?(true)?{
?jedis.watch("lock_test");
?String?val?=?jedis.hget("lock_test",?"locker");
?Integer?integer?=?Integer.valueOf(val);
?Transaction?tx?=?jedis.multi();
?tx.hset("lock_test",?"locker",?String.valueOf(integer?+?1));
?List<Object>?exec?=?tx.exec();
?if?(exec?==?null?||?exec.isEmpty())?{
?System.out.println(Thread.currentThread().getName()?+?":"?+?"Error:("?+?val?+?"=>"?+?(integer?+?1)?+?")");
?}?else?{
?String?values?=?"";
?for?(int?i?=?0;?i?<?exec.size();?i++)?{
?values?+=?exec.get(i).toString();
?}
?System.out.println(Thread.currentThread().getName()?+?":"?+?values?+?":("?+?val?+?"=>"?+?(integer?+?1)?+?")");
?break;
?}
?try?{
?Thread.sleep(10);
?}?catch?(InterruptedException?e)?{
?e.printStackTrace();
?}
?}
?jedis.close();
?threadsCountDownLatch.countDown();
?}
?};
?for?(int?i?=?0;?i?<?threahSize;?i++)?{
?new?Thread(handler).start();
?}
?//?等待所有并行子線程任務(wù)完成。
?try?{
?threadsCountDownLatch.await();
?}?catch?(InterruptedException?e)?{
?e.printStackTrace();
?}
?System.out.println("complete");
?val?=?jedis.hget("lock_test",?"locker");
?System.out.println(val);
?}
}

打印結(jié)果：

lock_test.locker的初始值為：0
Thread-8:0:(0=>1)
Thread-56:Error:(1=>2)
Thread-53:0:(1=>2)
Thread-25:Error:(0=>1)
Thread-18:Error:(0=>1)
Thread-3:Error:(0=>1)
Thread-30:Error:(2=>3)
Thread-11:Error:(2=>3)
Thread-9:Error:(0=>1)
Thread-63:0:(2=>3)
Thread-7:Error:(0=>1)
Thread-10:0:(3=>4)
Thread-34:0:(4=>5)
Thread-65:Error:(4=>5)
Thread-24:Error:(0=>1)
Thread-17:Error:(0=>1)
Thread-62:0:(5=>6)
Thread-29:Error:(6=>7)
Thread-61:0:(6=>7)
Thread-64:0:(7=>8)
Thread-16:Error:(0=>1)
Thread-19:Error:(8=>9)
Thread-6:Error:(0=>1)
Thread-28:Error:(0=>1)
Thread-21:Error:(0=>1)
Thread-14:Error:(0=>1)
Thread-20:Error:(0=>1)
Thread-5:Error:(0=>1)
Thread-13:Error:(0=>1)
Thread-15:Error:(0=>1)
Thread-22:Error:(0=>1)
Thread-4:Error:(0=>1)
Thread-12:Error:(0=>1)
Thread-23:Error:(0=>1)
Thread-54:Error:(0=>1)
Thread-57:Error:(0=>1)
Thread-26:0:(8=>9)
Thread-27:Error:(8=>9)
Thread-32:Error:(9=>10)
Thread-35:Error:(9=>10)
Thread-56:0:(9=>10)
Thread-33:Error:(10=>11)
Thread-50:0:(10=>11)
Thread-31:0:(11=>12)
Thread-38:0:(12=>13)
Thread-25:Error:(13=>14)
Thread-36:0:(13=>14)
Thread-39:Error:(14=>15)
Thread-14:0:(14=>15)
Thread-19:Error:(14=>15)
Thread-17:Error:(14=>15)
Thread-6:Error:(14=>15)
Thread-9:Error:(14=>15)
Thread-33:Error:(14=>15)
Thread-35:Error:(14=>15)
Thread-23:Error:(14=>15)
Thread-18:Error:(14=>15)
Thread-15:Error:(14=>15)
Thread-11:Error:(14=>15)
Thread-7:Error:(14=>15)
Thread-57:Error:(14=>15)
Thread-27:Error:(14=>15)
Thread-16:Error:(14=>15)
Thread-65:Error:(14=>15)
Thread-24:Error:(14=>15)
Thread-13:Error:(14=>15)
Thread-32:Error:(15=>16)
Thread-28:Error:(14=>15)
Thread-21:Error:(14=>15)
Thread-30:Error:(14=>15)
Thread-54:Error:(14=>15)
Thread-22:Error:(14=>15)
Thread-25:Error:(14=>15)
Thread-3:Error:(14=>15)
Thread-29:Error:(14=>15)
Thread-5:Error:(14=>15)
Thread-12:Error:(14=>15)
Thread-20:Error:(14=>15)
Thread-40:0:(15=>16)
Thread-4:Error:(14=>15)
Thread-41:0:(16=>17)
Thread-44:0:(17=>18)
Thread-45:0:(18=>19)
Thread-47:0:(19=>20)
Thread-43:0:(20=>21)
Thread-48:0:(21=>22)
Thread-37:0:(22=>23)
Thread-49:0:(23=>24)
Thread-55:0:(24=>25)
Thread-60:0:(25=>26)
Thread-42:0:(26=>27)
Thread-52:0:(27=>28)
Thread-46:0:(28=>29)
Thread-58:0:(29=>30)
Thread-51:0:(30=>31)
Thread-66:0:(31=>32)
Thread-59:0:(32=>33)
Thread-17:0:(33=>34)
Thread-19:Error:(33=>34)
Thread-39:Error:(33=>34)
Thread-28:0:(34=>35)
Thread-54:Error:(34=>35)
Thread-65:Error:(34=>35)
Thread-25:Error:(34=>35)
Thread-30:Error:(34=>35)
Thread-5:Error:(35=>36)
Thread-13:Error:(35=>36)
Thread-16:Error:(34=>35)
Thread-6:Error:(34=>35)
Thread-9:Error:(34=>35)
Thread-21:Error:(35=>36)
Thread-29:Error:(35=>36)
Thread-33:Error:(34=>35)
Thread-57:Error:(35=>36)
Thread-24:Error:(34=>35)
Thread-22:Error:(34=>35)
Thread-32:Error:(35=>36)
Thread-23:Error:(34=>35)
Thread-7:Error:(34=>35)
Thread-15:Error:(34=>35)
Thread-4:0:(35=>36)
Thread-20:Error:(35=>36)
Thread-12:Error:(35=>36)
Thread-35:0:(36=>37)
Thread-18:Error:(36=>37)
Thread-11:Error:(36=>37)
Thread-3:Error:(36=>37)
Thread-27:Error:(37=>38)
Thread-39:Error:(37=>38)
Thread-19:0:(37=>38)
Thread-7:Error:(38=>39)
Thread-33:0:(38=>39)
Thread-29:Error:(38=>39)
Thread-16:Error:(38=>39)
Thread-22:Error:(38=>39)
Thread-65:Error:(38=>39)
Thread-54:Error:(38=>39)
Thread-57:Error:(38=>39)
Thread-30:Error:(38=>39)
Thread-21:Error:(38=>39)
Thread-24:Error:(38=>39)
Thread-32:Error:(39=>40)
Thread-5:Error:(39=>40)
Thread-13:Error:(39=>40)
Thread-6:Error:(38=>39)
Thread-25:Error:(38=>39)
Thread-9:Error:(38=>39)
Thread-20:0:(39=>40)
Thread-12:Error:(39=>40)
Thread-15:Error:(38=>39)
Thread-23:Error:(38=>39)
Thread-18:Error:(40=>41)
Thread-3:Error:(40=>41)
Thread-27:0:(40=>41)
Thread-11:Error:(40=>41)
Thread-39:0:(41=>42)
Thread-7:Error:(42=>43)
Thread-54:0:(42=>43)
Thread-22:Error:(42=>43)
Thread-30:Error:(42=>43)
Thread-57:Error:(42=>43)
Thread-65:Error:(42=>43)
Thread-32:Error:(43=>44)
Thread-24:Error:(43=>44)
Thread-5:Error:(42=>43)
Thread-21:Error:(42=>43)
Thread-16:Error:(43=>44)
Thread-29:Error:(43=>44)
Thread-6:0:(43=>44)
Thread-9:Error:(43=>44)
Thread-23:Error:(43=>44)
Thread-25:Error:(43=>44)
Thread-15:Error:(43=>44)
Thread-12:Error:(43=>44)
Thread-13:Error:(44=>45)
Thread-11:0:(44=>45)
Thread-18:Error:(44=>45)
Thread-3:Error:(44=>45)
Thread-57:0:(45=>46)
Thread-7:Error:(45=>46)
Thread-22:Error:(45=>46)
Thread-30:Error:(45=>46)
Thread-9:0:(46=>47)
Thread-65:Error:(46=>47)
Thread-25:Error:(46=>47)
Thread-24:Error:(46=>47)
Thread-21:Error:(47=>48)
Thread-32:Error:(47=>48)
Thread-5:Error:(47=>48)
Thread-15:Error:(47=>48)
Thread-16:0:(47=>48)
Thread-29:Error:(47=>48)
Thread-12:Error:(48=>49)
Thread-23:Error:(47=>48)
Thread-13:0:(48=>49)
Thread-18:Error:(49=>50)
Thread-3:Error:(49=>50)
Thread-7:0:(49=>50)
Thread-30:Error:(49=>50)
Thread-22:Error:(49=>50)
Thread-25:0:(50=>51)
Thread-65:Error:(50=>51)
Thread-12:0:(51=>52)
Thread-21:Error:(51=>52)
Thread-32:Error:(52=>53)
Thread-24:Error:(52=>53)
Thread-29:Error:(52=>53)
Thread-5:Error:(52=>53)
Thread-23:Error:(52=>53)
Thread-15:Error:(52=>53)
Thread-18:0:(52=>53)
Thread-3:Error:(52=>53)
Thread-30:0:(53=>54)
Thread-22:Error:(53=>54)
Thread-65:0:(54=>55)
Thread-24:0:(55=>56)
Thread-21:Error:(55=>56)
Thread-32:Error:(55=>56)
Thread-5:0:(56=>57)
Thread-29:Error:(57=>58)
Thread-15:0:(57=>58)
Thread-23:Error:(57=>58)
Thread-3:0:(58=>59)
Thread-22:0:(59=>60)
Thread-32:0:(60=>61)
Thread-21:Error:(60=>61)
Thread-29:0:(61=>62)
Thread-23:Error:(61=>62)
Thread-21:0:(62=>63)
Thread-23:0:(63=>64)
complete
64

備注：實際應(yīng)用場景中我這里不是實現(xiàn)自增，上邊代碼自增目的：測試是否能夠在高并發(fā)下修改同一個key時實現(xiàn)鎖的功能。

實際應(yīng)用：高并發(fā)使用redis同一個key存儲統(tǒng)計TOPN結(jié)果

需求：

1）擁有多個記錄，每條記錄數(shù)據(jù)格式：日期，統(tǒng)計指標1，統(tǒng)計指標2，統(tǒng)計指標3，統(tǒng)計指標4

2）要求分別統(tǒng)計出4個指標的最大值，并記錄各自指標最大值時對應(yīng)的記錄。

3）記錄中各個字段的模擬公式：

//?數(shù)據(jù)格式:
//?第一列：日期
//?第二列：f(x)?=?x*0.7+1(x自然數(shù))?最大值?45.1
//?第三列：f（x）=?-x*x+20x+1(自然數(shù))?a=-1,b=20,c=1?，?當x=-b/2a時?y?最大值：-10*10+20*10+1=101
//?第四列：f（x）=?-x*x+30x+1(自然數(shù))?a=-1,b=30,c=1?，?當x=-b/2a時?y?最大值：-15*15+30*15+1=445-225+1=221
//?第五列：f（x）=?640/(x+1)(x自然數(shù))?最大值?640

使用mutil+watch實現(xiàn)：

首先，把最終統(tǒng)計結(jié)果存儲到redis的key（lock_test）中，lock_test是一個hash類型，其中存儲四個鍵值對，每個鍵值對分別存儲各自的指標最大值時對應(yīng)的記錄。

指標配置項存儲到FeildConfig.java

?static?class?FieldConfig?{
?private?String?key;
?private?Integer?index;
?public?String?getKey()?{
?return?key;
?}
?public?void?setKey(String?key)?{
?this.key?=?key;
?}
?public?Integer?getIndex()?{
?return?index;
?}
?public?void?setIndex(Integer?index)?{
?this.index?=?index;
?}
?public?FieldConfig(String?key,?Integer?index)?{
?super();
?this.key?=?key;
?this.index?=?index;
?}
?}

在測試類的static構(gòu)造函數(shù)中初始化各自指標在一條記錄的中索引位置，及一共包含的指標類型：

public?class?Test_Lock3?{
?。。。
?final?static?List<FieldConfig>?keys?=?new?ArrayList<FieldConfig>();
?static?{
?keys.add(new?FieldConfig("101",?1));
?keys.add(new?FieldConfig("102",?2));
?keys.add(new?FieldConfig("103",?3));
?keys.add(new?FieldConfig("104",?4));
?}
?。。。
}

備注：101代表指標1，對應(yīng)在被統(tǒng)計記錄中的第1索引位置（備注：這里索引是對記錄按照“,”分割后的數(shù)組索引位置）。

制作測試數(shù)據(jù)：

?List<String>?dataItems=new?ArrayList<String>();
?//?數(shù)據(jù)格式:
?//?第一列：日期
?//?第二列：f(x)?=?x*0.7+1(x自然數(shù))?最大值?45.1
?//?第三列：f（x）=?-x*x+20x+1(自然數(shù))?a=-1,b=20,c=1?，?當x=-b/2a時?y?最大值：-10*10+20*10+1=101
?//?第四列：f（x）=?-x*x+30x+1(自然數(shù))?a=-1,b=30,c=1?，?當x=-b/2a時?y?最大值：-15*15+30*15+1=445-225+1=221
?//?第五列：f（x）=?640/(x+1)(x自然數(shù))?最大值?640?
?for(int?x=0;x<threahSize;x++){
?String?dataItem?=?"2018-07-29?00:00:00,"?+?(x*0.7d+1)?+?","?+?(-1d*x*x+20*x+1)?+?","?+?(-1d*x*x+30*x+1)?+?","?+?(640d/(x+1));
?dataItems.add(dataItem);
?}

以下是整體測試代碼：

package?com.dx.es;
import?java.util.ArrayList;
import?java.util.HashMap;
import?java.util.List;
import?java.util.Map;
import?java.util.concurrent.CountDownLatch;
import?redis.clients.jedis.Jedis;
import?redis.clients.jedis.JedisPool;
import?redis.clients.jedis.Transaction;
public?class?Test_Lock3?{
?final?static?JedisPool?pool?=?RedisUtil.getPool();
?final?static?List<FieldConfig>?keys?=?new?ArrayList<FieldConfig>();
?static?{
?keys.add(new?FieldConfig("101",?1));
?keys.add(new?FieldConfig("102",?2));
?keys.add(new?FieldConfig("103",?3));
?keys.add(new?FieldConfig("104",?4));
?}
?public?static?void?main(String[]?args)?{
?int?threahSize?=?64;
?final?CountDownLatch?threadsCountDownLatch?=?new?CountDownLatch(threahSize);
?Jedis?jedis?=?pool.getResource();
?jedis.del("lock_test");
?
?List<String>?dataItems=new?ArrayList<String>();
?//?數(shù)據(jù)格式:
?//?第一列：日期
?//?第二列：f(x)?=?x*0.7+1(x自然數(shù))?最大值?45.1
?//?第三列：f（x）=?-x*x+20x+1(自然數(shù))?a=-1,b=20,c=1?，?當x=-b/2a時?y?最大值：-10*10+20*10+1=101
?//?第四列：f（x）=?-x*x+30x+1(自然數(shù))?a=-1,b=30,c=1?，?當x=-b/2a時?y?最大值：-15*15+30*15+1=445-225+1=221
?//?第五列：f（x）=?640/(x+1)(x自然數(shù))?最大值?640?
?for(int?x=0;x<threahSize;x++){
?String?dataItem?=?"2018-07-29?00:00:00,"?+?(x*0.7d+1)?+?","?+?(-1d*x*x+20*x+1)?+?","?+?(-1d*x*x+30*x+1)?+?","?+?(640d/(x+1));
?dataItems.add(dataItem);
?}
?
?
?for?(int?i?=?0;?i?<?threahSize;?i++)?{
?Jedis?jedisT?=?pool.getResource();
?
?Runnable?handler?=?new?MyRunable(jedisT,?threadsCountDownLatch,?dataItems.get(i));
?new?Thread(handler).start();
?}
?//?等待所有并行子線程任務(wù)完成。
?try?{
?threadsCountDownLatch.await();
?}?catch?(InterruptedException?e)?{
?e.printStackTrace();
?}
?System.out.println("complete");
?Map<String,?String>?values?=?jedis.hgetAll("lock_test");
?jedis.close();
?System.out.println(values);
?}
?static?class?MyRunable?implements?Runnable?{
?private?Jedis?jedis?=?null;
?private?CountDownLatch?threadsCountDownLatch?=?null;
?private?String?newLine?=?null;
?public?MyRunable(Jedis?jedis,?CountDownLatch?threadsCountDownLatch,?String?newLine)?{
?this.jedis?=?jedis;
?this.threadsCountDownLatch?=?threadsCountDownLatch;
?this.newLine?=?newLine;
?}
?public?void?run()?{
?while?(true)?{
?this.jedis.watch("lock_test");
?Map<String,?String>?newValues?=?new?HashMap<String,?String>();
?Map<String,?String>?oldValues?=?this.jedis.hgetAll("lock_test");
?
?String?newValueStr="";
?for?(FieldConfig?key?:?keys)?{
?if?(oldValues.containsKey(key.getKey()))?{
?Double?oldValue?=?Double.valueOf(oldValues.get(key.getKey()).split(",")[key.getIndex()]);
?Double?newValue?=?Double.valueOf(newLine.split(",")[key.getIndex()]);
?if?(newValue?>?oldValue)?{
?newValues.put(key.getKey(),?newLine);
?newValueStr=newLine;
?}?else?{
?newValues.put(key.getKey(),?oldValues.get(key.getKey()));
?newValueStr=oldValues.get(key.getKey());
?}
?}?else?{
?newValues.put(key.getKey(),?newLine);
?newValueStr=newLine;
?}
?}
?Transaction?tx?=?this.jedis.multi();
?tx.hmset("lock_test",?newValues);
?List<Object>?exec?=?tx.exec();
?if?(exec?==?null?||?exec.isEmpty())?{
?//System.out.println(Thread.currentThread().getName()?+?":"?+?"Error:("?+?oldValueStr?+?"->"+newValueStr+")");
?}?else?{
?String?values?=?"";
?for?(int?i?=?0;?i?<?exec.size();?i++)?{
?values?+=?exec.get(i).toString();
?}
?System.out.println(Thread.currentThread().getName()?+?":"?+?values?+?":("?+?newLine?+"->"+newValueStr+")");
?break;
?}
?try?{
?Thread.sleep(10);
?}?catch?(InterruptedException?e)?{
?e.printStackTrace();
?}
?}
?this.jedis.close();
?this.threadsCountDownLatch.countDown();
?}
?}
?static?class?FieldConfig?{
?private?String?key;
?private?Integer?index;
?public?String?getKey()?{
?return?key;
?}
?public?void?setKey(String?key)?{
?this.key?=?key;
?}
?public?Integer?getIndex()?{
?return?index;
?}
?public?void?setIndex(Integer?index)?{
?this.index?=?index;
?}
?public?FieldConfig(String?key,?Integer?index)?{
?super();
?this.key?=?key;
?this.index?=?index;
?}
?}
}

測試：

Thread-23:OK:(2018-07-29?00:00:00,15.0,1.0,201.0,30.476190476190474->2018-07-29?00:00:00,15.0,1.0,201.0,30.476190476190474)
Thread-29:OK:(2018-07-29?00:00:00,19.2,-155.0,105.0,23.703703703703702->2018-07-29?00:00:00,15.0,1.0,201.0,30.476190476190474)
Thread-33:OK:(2018-07-29?00:00:00,22.0,-299.0,1.0,20.64516129032258->2018-07-29?00:00:00,15.0,1.0,201.0,30.476190476190474)
Thread-24:OK:(2018-07-29?00:00:00,15.7,-20.0,190.0,29.09090909090909->2018-07-29?00:00:00,15.0,1.0,201.0,30.476190476190474)
Thread-36:OK:(2018-07-29?00:00:00,24.099999999999998,-428.0,-98.0,18.823529411764707->2018-07-29?00:00:00,15.0,1.0,201.0,30.476190476190474)
Thread-32:OK:(2018-07-29?00:00:00,21.299999999999997,-260.0,30.0,21.333333333333332->2018-07-29?00:00:00,15.0,1.0,201.0,30.476190476190474)
Thread-39:OK:(2018-07-29?00:00:00,26.2,-575.0,-215.0,17.2972972972973->2018-07-29?00:00:00,15.0,1.0,201.0,30.476190476190474)
Thread-40:OK:(2018-07-29?00:00:00,26.9,-628.0,-258.0,16.842105263157894->2018-07-29?00:00:00,15.0,1.0,201.0,30.476190476190474)
Thread-25:OK:(2018-07-29?00:00:00,16.4,-43.0,177.0,27.82608695652174->2018-07-29?00:00:00,15.0,1.0,201.0,30.476190476190474)
Thread-3:OK:(2018-07-29?00:00:00,1.0,1.0,1.0,640.0->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-16:OK:(2018-07-29?00:00:00,10.1,92.0,222.0,45.714285714285715->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-21:OK:(2018-07-29?00:00:00,13.6,37.0,217.0,33.68421052631579->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-45:OK:(2018-07-29?00:00:00,30.4,-923.0,-503.0,14.883720930232558->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-28:OK:(2018-07-29?00:00:00,18.5,-124.0,126.0,24.615384615384617->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-46:OK:(2018-07-29?00:00:00,31.099999999999998,-988.0,-558.0,14.545454545454545->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-12:OK:(2018-07-29?00:00:00,7.3,100.0,190.0,64.0->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-34:OK:(2018-07-29?00:00:00,22.7,-340.0,-30.0,20.0->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-49:OK:(2018-07-29?00:00:00,33.199999999999996,-1195.0,-735.0,13.617021276595745->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-50:OK:(2018-07-29?00:00:00,33.9,-1268.0,-798.0,13.333333333333334->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-52:OK:(2018-07-29?00:00:00,35.3,-1420.0,-930.0,12.8->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-53:OK:(2018-07-29?00:00:00,36.0,-1499.0,-999.0,12.549019607843137->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-54:OK:(2018-07-29?00:00:00,36.699999999999996,-1580.0,-1070.0,12.307692307692308->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-55:OK:(2018-07-29?00:00:00,37.4,-1663.0,-1143.0,12.075471698113208->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-56:OK:(2018-07-29?00:00:00,38.099999999999994,-1748.0,-1218.0,11.851851851851851->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-57:OK:(2018-07-29?00:00:00,38.8,-1835.0,-1295.0,11.636363636363637->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-58:OK:(2018-07-29?00:00:00,39.5,-1924.0,-1374.0,11.428571428571429->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-59:OK:(2018-07-29?00:00:00,40.199999999999996,-2015.0,-1455.0,11.228070175438596->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-60:OK:(2018-07-29?00:00:00,40.9,-2108.0,-1538.0,11.03448275862069->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-61:OK:(2018-07-29?00:00:00,41.599999999999994,-2203.0,-1623.0,10.847457627118644->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-62:OK:(2018-07-29?00:00:00,42.3,-2300.0,-1710.0,10.666666666666666->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-63:OK:(2018-07-29?00:00:00,43.0,-2399.0,-1799.0,10.491803278688524->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-64:OK:(2018-07-29?00:00:00,43.699999999999996,-2500.0,-1890.0,10.32258064516129->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-65:OK:(2018-07-29?00:00:00,44.4,-2603.0,-1983.0,10.158730158730158->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-11:OK:(2018-07-29?00:00:00,6.6,97.0,177.0,71.11111111111111->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-41:OK:(2018-07-29?00:00:00,27.599999999999998,-683.0,-303.0,16.41025641025641->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-47:OK:(2018-07-29?00:00:00,31.799999999999997,-1055.0,-615.0,14.222222222222221->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-37:OK:(2018-07-29?00:00:00,24.799999999999997,-475.0,-135.0,18.285714285714285->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-48:OK:(2018-07-29?00:00:00,32.5,-1124.0,-674.0,13.91304347826087->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-5:OK:(2018-07-29?00:00:00,2.4,37.0,57.0,213.33333333333334->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-42:OK:(2018-07-29?00:00:00,28.299999999999997,-740.0,-350.0,16.0->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-8:OK:(2018-07-29?00:00:00,4.5,76.0,126.0,106.66666666666667->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-9:OK:(2018-07-29?00:00:00,5.199999999999999,85.0,145.0,91.42857142857143->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-43:OK:(2018-07-29?00:00:00,29.0,-799.0,-399.0,15.609756097560975->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-7:OK:(2018-07-29?00:00:00,3.8,65.0,105.0,128.0->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-44:OK:(2018-07-29?00:00:00,29.7,-860.0,-450.0,15.238095238095237->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-18:OK:(2018-07-29?00:00:00,11.5,76.0,226.0,40.0->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-20:OK:(2018-07-29?00:00:00,12.899999999999999,52.0,222.0,35.55555555555556->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-15:OK:(2018-07-29?00:00:00,9.399999999999999,97.0,217.0,49.23076923076923->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-27:OK:(2018-07-29?00:00:00,17.799999999999997,-95.0,145.0,25.6->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-17:OK:(2018-07-29?00:00:00,10.799999999999999,85.0,225.0,42.666666666666664->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-10:OK:(2018-07-29?00:00:00,5.8999999999999995,92.0,162.0,80.0->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-66:OK:(2018-07-29?00:00:00,45.099999999999994,-2708.0,-2078.0,10.0->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-19:OK:(2018-07-29?00:00:00,12.2,65.0,225.0,37.64705882352941->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-26:OK:(2018-07-29?00:00:00,17.099999999999998,-68.0,162.0,26.666666666666668->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-4:OK:(2018-07-29?00:00:00,1.7,20.0,30.0,320.0->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-35:OK:(2018-07-29?00:00:00,23.4,-383.0,-63.0,19.393939393939394->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-22:OK:(2018-07-29?00:00:00,14.299999999999999,20.0,210.0,32.0->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-31:OK:(2018-07-29?00:00:00,20.599999999999998,-223.0,57.0,22.06896551724138->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-51:OK:(2018-07-29?00:00:00,34.599999999999994,-1343.0,-863.0,13.061224489795919->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-30:OK:(2018-07-29?00:00:00,19.9,-188.0,82.0,22.857142857142858->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-6:OK:(2018-07-29?00:00:00,3.0999999999999996,52.0,82.0,160.0->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-14:OK:(2018-07-29?00:00:00,8.7,100.0,210.0,53.333333333333336->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-13:OK:(2018-07-29?00:00:00,8.0,101.0,201.0,58.18181818181818->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
Thread-38:OK:(2018-07-29?00:00:00,25.5,-524.0,-174.0,17.77777777777778->2018-07-29?00:00:00,1.0,1.0,1.0,640.0)
complete
{
101=2018-07-29?00:00:00,45.099999999999994,-2708.0,-2078.0,10.0,?
102=2018-07-29?00:00:00,8.0,101.0,201.0,58.18181818181818,
103=2018-07-29?00:00:00,11.5,76.0,226.0,40.0,
104=2018-07-29?00:00:00,1.0,1.0,1.0,640.0
}

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Redis：解決分布式高并發(fā)修改同一個Key的問題

Redis：解決分布式高并發(fā)修改同一個Key的問題


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