# onBufferEmpty
當緩存區低于最低水位線時觸發此事件。
~~~
function onBufferEmpty(Swoole\Client $cli);
~~~
* 設置`client->buffer_low_watermark`來控制緩存區低水位線
* 觸發此事件后，表明當前發送隊列中的數據已被發出，可以繼續向服務器端發送數據
- 序言
- 入門指引
- 環境依賴
- 編譯安裝
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- Cygwin
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- 1.9.14 使用異步客戶端超時機制
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- 1.7.3 固定包頭+包體協議自動分包
- 1.7.3 onTask直接return取代finish函數
- 1.7.2 swoole_process多進程模塊的使用
- 1.7.2 task進程使用消息隊列
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- onStart
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- 高級特性
- 改變Worker進程的用戶/組
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- Server中對象的4層生命周期
- 在worker進程內監聽一個Server端口
- 在php-fpm/apache中使用task功能
- 常見問題
- 為什么不要send完后立即close
- 如何在回調函數中訪問外部的變量
- 是否可以共用1個redis或mysql連接
- 關于onConnect/onReceive/onClose順序
- 4種PHP回調函數風格
- 不同的Server程序實例間如何通信
- 錯誤信息：ERROR (9006)
- eventLoop has already been created. unable to create swoole_server
- 壓力測試
- 并發10萬TCP連接的測試
- PHP7+Swoole/Nginx/Golang性能對比
- 全球Web框架權威性能測試 Techempower Web Framework Benchmarks
- Coroutine
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- Coroutine\Channel
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- Coroutine\Channel->stats
- Coroutine\Channel->close
- Coroutine\Channel->length
- Coroutine\Channel->isEmpty
- Coroutine\Channel->isFull
- Coroutine\Channel->$capacity
- Coroutine\Channel->$errCode
- Coroutine\Client
- Coroutine\Client->connect
- Coroutine\Client->send
- Coroutine\Client->recv
- Coroutine\Client->close
- Coroutine\Client->peek
- Coroutine\Http\Client
- 屬性列表
- Coroutine\Http\Client->get
- Coroutine\Http\Client->post
- Coroutine\Http\Client->upgrade
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- Coroutine\Http\Client->recv
- Coroutine\Http\Client->addFile
- Coroutine\Http\Client->addData
- Coroutine\Http\Client->download
- Coroutine\Http2\Client
- Coroutine\Http2\Client->__construct
- Coroutine\Http2\Client->set
- Coroutine\Http2\Client->connect
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- Coroutine\Http2\Client->write
- Coroutine\Http2\Client->recv
- Coroutine\Http2\Client->close
- Coroutine\Redis
- Coroutine\Redis::__construct
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- 事務模式
- 訂閱模式
- Coroutine\Socket
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- Coroutine\MySQL
- 屬性列表
- Coroutine\MySQL->connect
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- Coroutine\MySQL->escape
- Coroutine\MySQL->begin
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- Coroutine\MySQL\Statement->nextResult
- Coroutine\PostgreSQL
- Coroutine\PostgreSQL->connect
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- Coroutine\PostgreSQL->affectedRows
- Coroutine\PostgreSQL->numRows
- Coroutine\PostgreSQL->fetchObject
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- Coroutine\PostgreSQL->fetchArray
- Coroutine\PostgreSQL->fetchRow
- Coroutine\PostgreSQL->metaData
- Coroutine\PostgreSQL->prepare
- Server
- 并發調用
- setDefer 機制
- 子協程+通道
- 實現原理
- 協程與線程
- 發送數據協程調度
- 協程內存開銷
- 4.0 協程實現原理
- 協程客戶端超時規則
- 協程執行流程
- 常見問題
- 運行中出現 Fatal error: Maximum function nesting level of '1000' reached, aborting!
- 為什么只能在回調函數中使用協程客戶端
- 支持協程的回調方法列表
- 錯誤信息： XXXX client has already been bound to another coroutine
- Swoole4 協程與 PHP 的 Yield/Generator 協程有什么區別
- Swoole4 協程與 Go 協程有哪些區別
- 編程須知
- 在多個協程間共用同一個協程客戶端
- 禁止使用協程 API 的場景（2.x 版本）
- 使用類靜態變量/全局變量保存上下文
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- 擴展組件
- MongoDB
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- Runtime
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- Buffer
- swoole_buffer->__construct
- swoole_buffer->append
- swoole_buffer->substr
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- swoole_buffer->expand
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- Table
- Table->__construct
- Table->column
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- Atomic
- swoole_atomic->__construct
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- mmap
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- Channel
- Channel->__construct
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- swoole_serialize::pack
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- Http\Server
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- Http\Response->gzip
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- 配置選項
- upload_tmp_dir
- http_parse_post
- document_root
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- 常見問題
- CURL發送POST請求服務器端超時
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- GET/POST請求的最大尺寸
- WebSocket\Server
- 回調函數
- onHandShake
- onOpen
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- 常見問題
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- WebSocket\Frame
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- 方法
- Redis\Server->setHandler
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- 常量
- Process
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- Process\Pool::__construct
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- Client
- 方法列表
- swoole_client::__construct
- swoole_client->set
- swoole_client->on
- swoole_client->connect
- swoole_client->isConnected
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- swoole_client->getSockName
- swoole_client->getPeerName
- swoole_client->getPeerCert
- swoole_client->send
- swoole_client->sendto
- swoole_client->sendfile
- swoole_client->recv
- swoole_client->close
- swoole_client->sleep
- swoole_client->wakeup
- swoole_client->enableSSL
- 回調函數
- onConnect
- onError
- onReceive
- onClose
- onBufferFull
- onBufferEmpty
- 屬性列表
- swoole_client->errCode
- swoole_client->sock
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- 并行
- swoole_client_select
- TCP客戶端異步連接
- SWOOLE_KEEP建立TCP長連接
- 常量
- 配置選項
- ssl_verify_peer
- ssl_host_name
- ssl_cafile
- ssl_capath
- package_length_func
- http_proxy_host
- 常見問題
- Event
- swoole_event_add
- swoole_event_set
- swoole_event_isset
- swoole_event_write
- swoole_event_del
- swoole_event_exit
- swoole_event_defer
- swoole_event_cycle
- swoole_event_wait
- swoole_event_dispatch
- 常見問題
- epoll_wait 偶爾會用很長時間
- 異步回調
- 異步文件系統IO
- swoole_async_readfile
- swoole_async_writefile
- swoole_async_read
- swoole_async_write
- swoole_async_dns_lookup
- swoole_async::exec
- 異步MySQL客戶端
- swoole_mysql->__construct
- swoole_mysql->on
- swoole_mysql->connect
- swoole_mysql->escape
- swoole_mysql->query
- swoole_mysql->begin
- swoole_mysql->commit
- swoole_mysql->rollback
- swoole_mysql->close
- 異步Redis客戶端
- swoole_redis->__construct
- swoole_redis->on
- swoole_redis->connect
- swoole_redis->__call
- swoole_redis->close
- 異步Http/WebSocket客戶端
- swoole_http_client->__construct
- swoole_http_client->set
- swoole_http_client->setMethod
- swoole_http_client->setHeaders
- swoole_http_client->setCookies
- swoole_http_client->setData
- swoole_http_client->addFile
- swoole_http_client->get
- swoole_http_client->post
- swoole_http_client->upgrade
- swoole_http_client->push
- swoole_http_client->execute
- swoole_http_client->download
- swoole_http_client->close
- 異步Http2.0客戶端
- swoole_http2_client->__construct
- swoole_http2_client->get
- swoole_http2_client->post
- swoole_http2_client->setHeaders
- swoole_http2_client->setCookies
- 高級
- Swoole的實現
- Reactor線程
- Manager進程
- Worker進程
- Reactor、Worker、TaskWorker的關系
- Task/Finish特性的用途
- 在php-fpm或apache中使用swoole
- Swoole異步與同步的選擇
- TCP/UDP壓測工具
- swoole服務器如何做到無人值守100%可用
- MySQL的連接池、異步、斷線重連
- PHP中哪些函數是同步阻塞的
- 守護進程程序常用數據結構
- 隊列（Queue）
- 堆（Heap）
- 定長數組（SplFixedArray）
- 使用jemalloc優化swoole內存分配性能
- C開發者如何使用Swoole
- C++開發者如何使用Swoole
- 使用systemd管理swoole服務
- 網卡中斷設置
- 將Swoole靜態編譯內嵌到PHP
- 異步回調程序內存管理
- 日志等級控制
- 使用 asan 內存檢測
- Windows編譯
- Swoole協程之旅-前篇
- Swoole協程之旅-中篇
- Swoole協程之旅-后篇
- 協程CPU密集場景調度實現
- 其他
- 函數列表
- swoole_set_process_name
- swoole_version
- swoole_strerror
- swoole_errno
- swoole_get_local_ip
- swoole_clear_dns_cache
- swoole_get_local_mac
- swoole_cpu_num
- swoole_last_error
- Swoole社區
- Swoole技術會議
- 工作組（Working Groups）
- 參與開源項目指引
- 捐贈Swoole項目
- 加入Swoole開發組
- 非協程特性獨立擴展 （swoole_async）
- 附錄：Linux信號列表
- 附錄：Linux錯誤碼(errno)列表
- 附錄：Swoole錯誤碼列表
- 附錄：TCP連接的狀態
- 附錄：tcpdump抓包工具的使用
- 附錄：strace工具的使用
- 附錄：gdb工具的使用
- 附錄：lsof工具的使用
- 附錄：perf工具的使用
- 附錄：編譯PHP擴展的相關工具
- 備用：已移除的歷史特性
- swoole_server->handler
- task_worker_max
- swoole_server->addtimer
- swoole_server->deltimer
- onTimer
- swoole_timer_add
- swoole_timer_del
- swoole_get_mysqli_sock
- swoole_mysql_query
- onMasterConnect
- onMasterClose
- Nginx/Golang/Swoole/Node.js的性能對比
- Coroutine::call_user_func
- Coroutine::call_user_func_array
- Coroutine\Channel::select
- task_async
- 歷史：版本更新記錄（1.x）
- 1.10.3
- 1.10.2
- 1.10.1
- 1.10.0
- 1.9.23
- 1.9.22
- 1.9.19
- 1.9.18
- 1.9.17
- 1.9.16
- 1.9.15
- 1.9.14
- 1.9.12
- 1.9.11
- 1.9.9
- 1.9.7
- 1.9.6
- 1.9.5
- 1.9.4
- 1.9.3
- 1.9.2
- 1.9.1
- 1.9.0
- 1.8.13
- 1.8.12
- 1.8.11
- 1.8.10
- 1.8.9
- 1.8.8
- 1.8.7
- 1.8.6
- 1.8.5
- 1.8.4
- 1.8.3
- 1.8.2
- 1.8.1
- 1.8.0
- 1.7.22
- 1.7.21
- 1.7.20
- 1.7.19
- 1.7.18
- 1.7.17
- 1.7.16
- 1.7.15
- 1.7.14
- 1.7.13
- 1.7.12
- 1.7.11
- 1.7.10
- 1.7.9
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