php 并发 读写文件冲突的解决实例

php 并发 读写文件冲突的解决方案

解决方案核心思想：

增加 临时写入文件数目，对众多临时文件文件进行随机读写，以降低并发的可能性。

实例：

在对用户访问日志进行记录时，这种方案似乎被采用的比较多。先前需要定义一个随机空间，空间越大，并发的的可能性就越小，这里假设随机读写空间为[1-500],那么我们的日志文件的分布就为log1~到log500不等。每一次用户访问，都将数据随机写到log1~log500之间的任一文件。在同一时刻，有2个进程进行记录日志，A进程可能是更新的log32文件，而B进程呢？则此时更新的可能就为log399.要知道，如果要让B进程也操作log32,概率基本上为1/500,差不多约等于零。在需要对访问日志进行分析时，这里我们只需要先将这些日志合并，再进行分析即可。使用这种方案来记录日志的一个好处时，进程操作排队的可能性比较小，可以使进程很迅速的完成每一次操作。

php代码实例：

<?php error_reporting(E_ALL || ~E_NOTICE);//报错屏蔽设置date_default_timezone_set('PRC');//设置默认时区$randam1 = rand(1,10);$randam2 = rand(1,10);$file1 = "spark_sql_data"."_".$randam1.".json";$file2 = "spark_sql_tanzhen"."_".$randam2.".json";$fp1 = fopen($file1,"a+");$fp2 = fopen($file2,"a+");//..........//中间逻辑代码//.......... flock($fp1,LOCK_EX); fwrite($fp1,$detail_infor_json);flock($fp1,LOCK_UN);flock($fp2,LOCK_EX);fwrite($fp2,$tanzhen_infor_json);flock($fp2,LOCK_UN); fclose($file1); fclose($file2);?>

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结果展示：

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完整代码展示（高端玩家选读）：

<?php error_reporting(E_ALL || ~E_NOTICE);//报错屏蔽设置date_default_timezone_set('PRC');//设置默认时区$randam1 = rand(1,10);$randam2 = rand(1,10);$file1 = "spark_sql_data"."_".$randam1.".json";$file2 = "spark_sql_tanzhen"."_".$randam2.".json";$fp1 = fopen($file1,"a+");$fp2 = fopen($file2,"a+");/* 本例用到的数据： data={"id":"0029c591","mmac":"5e:cf:7f:29:c5:91","rate":"1","wssid":"datasky1","wmac":"00:0c:43:76:20:59","time":"Tue Feb 21 08:13:31 2017", "lat":"30.747988","lon":"103.973152","addr":"四川省成都市郫县犀浦镇两河新街;围城南路与兴业南街路口东","data":[{"mac":"a4:56:02:61:7f:57","rssi":"-91 ","range":"91.5"},{"mac":"8c:a6:df:62:2d:3d","rssi":"-93","range":"108.5"},{"mac":"a4:56:02:71:be:b3","rssi":"-96","range":"140.1"},{"mac":" cc:34:29:97:4d:0d","rssi":"-95","range":"128.6"},{"mac":"44:33:4c:aa:71:82","rssi":"-94","range":"118.1"},{"mac":"b0:48:7a:5a:10:f8","rssi": "-86","range":"59.7"},{"mac":"a8:57:4e:9d:ca:d8","rssi":"-96","range":"140.1"},{"mac":"5e:cf:7f:93:3d:0e","rssi":"-56","range":"4.6"},{"mac ":"5e:cf:7f:93:3d:0f","rssi":"-58","range":"5.5"},{"mac":"5e:cf:7f:93:3d:10","rssi":"-63","range":"8.4"},{"mac":"5e:cf:7f:93:3d:0b","rssi":" -68","range":"12.9"},{"mac":"5e:cf:7f:93:3d:0c","rssi":"-53","range":"3.5"},{"mac":"5e:cf:7f:93:3d:0d","rssi":"-69","range":"14.0"},{"mac":" e4:f3:f5:24:2c:d8","rssi":"-89","range":"77.1"},{"mac":"14:cf:92:8a:8f:f0","rssi":"-96","range":"140.1"}]}POST /dsky HTTP/1.0*/ // 参数定义 $flow_range = 10; $customer_range = 3; $insert_interval = 60;//插入相同用户的时间间隔//获取来自探针通过 post传值方式 传过来的数据$data=$_POST['data']; //解析数据$obj=json_decode($data,TRUE); $id = $obj['id']; $mmac = $obj['mmac']; $rate = $obj['rate']; $wssid = $obj['wssid']; $wmac = $obj['wmac']; //$time = $obj['time']; $time = time(); $lat = $obj['lat']; $lon = $obj['lon']; $addr = $obj['addr']; $detail_data = $obj['data']; //--得到 Json_list 数组长度 $num=count($obj['data']); $i=0;//循环变量 $j=0;//在店人数统计$k=0;//人流量统计$detail_infor_json = "";//--遍历数组，将对应信息输出 for ($i;$i<$num;$i++) {   $mac=$detail_data [$i]["mac"];   $rssi=$detail_data [$i]["rssi"];  $range=pow(10,(float)((int)abs($rssi)-59)/(10*2.0)); $ts=$detail_data [$i]["ts"]; $tmc=$detail_data [$i]["tmc"];  $tc=$detail_data [$i]["tc"];   $ds=$detail_data [$i]["ds"];  $essid1=$detail_data [$i]["essid1"];  $essid2=$detail_data [$i]["essid2"];  $essid3=$detail_data [$i]["essid3"]; $essid4=$detail_data [$i]["essid4"]; $essid5=$detail_data [$i]["essid5"];  $essid6=$detail_data [$i]["essid6"];  if((int)$range<= $flow_range&&(int)$range>=$customer_range){     $k++;//客流量统计 } //若检测到信号距离小于设定值，则认定为在店有效数据，即插入数据库 if((float)$range<= $customer_range){     $j++;//在店人数统计     $detail_info["tanzhen_id"] = $id ;     $detail_info["time"] = $time ;     $detail_info["mac"] = $mac ;     $detail_info["rssi"] = $rssi ;     $detail_info["range"] = number_format($range,2) ;     $detail_info["ts"] = $ts ;     $detail_info["tmc"] = $tmc ;     $detail_info["tc"] = $tc ;     $detail_info["ds"] = $ds ;     $detail_info["essid1"] = $essid1 ;     $detail_info["essid2"] = $essid2 ;     $detail_info["essid3"] = $essid3 ;     $detail_info["essid4"] = $essid4 ;     $detail_info["essid5"] = $essid5 ;     $detail_info["essid6"] = $essid6 ;     $detail_infor_json = $detail_infor_json.json_encode($detail_info,TRUE)."\n"; } }        flock($fp1,LOCK_EX);     fwrite($fp1,$detail_infor_json);     flock($fp1,LOCK_UN);     $tanzhen_info["id"] = $id ;     $tanzhen_info["mmac"] = $mmac ;     $tanzhen_info["rate"] = $rate ;     $tanzhen_info["wssid"] = $wssid ;     $tanzhen_info["time"] = $time ;     $tanzhen_info["lat"] = $lat ;     $tanzhen_info["lon"] = $lon ;     $tanzhen_info["addr"] = $addr ;     $tanzhen_info["flow_num"] = $k ;     $tanzhen_info["customer_num"] = $j ;     $tanzhen_infor_json = json_encode($tanzhen_info,TRUE);     $tanzhen_infor_json=$tanzhen_infor_json."\n";     flock($fp2,LOCK_EX);     fwrite($fp2,$tanzhen_infor_json);     flock($fp2,LOCK_UN); fclose($file1); fclose($file2);?>