爲什麼要雲原生？

{"type":"doc","content":[{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"1.寫在前面"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"目前業界對於雲原生的聲音越來越大，很多業界大牛給雲原生布道，但是對於普通程序員來說，總有一些問題在困擾着，雲原生到底是什麼？雲原生有什麼好？怎麼才能做到雲原生？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"本文希望探討雲原生的誕生場景。以及解決的問題。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"2.服務的發展之路"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"簡單總結下過去十多年服務的演變之路，總體可以分爲如下3個階段"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"【單體架構階段】->【RPC架構階段】->【微服務架構階段】"}]},{"type":"heading","attrs":{"align":null,"level":5},"content":[{"type":"text","text":"2.1 單體架構階段"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"在互聯網之前，傳統軟件公司時候"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"當網站流量很小時，只需一個應用，將所有功能都部署在一起，以減少部署節點和成本。"}]},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/35/3536940937aaf8858d5bb4fdf15d6690.png","alt":null,"title":"","style":[{"key":"width","value":"50%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"heading","attrs":{"align":null,"level":5},"content":[{"type":"text","text":"2.2 RPC架構階段"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"隨之互聯網的發展，流量激增，單體應用面臨着許許多多的問題，例如："}]},{"type":"numberedlist","attrs":{"start":1,"normalizeStart":1},"content":[{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":1,"number":1,"align":null,"origin":null},"content":[{"type":"text","text":"單體應用增加機器以及無法帶來性能上的提升"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":1,"number":2,"align":null,"origin":null},"content":[{"type":"text","text":"代碼量巨大，啓動服務都要幾分鐘"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":1,"number":3,"align":null,"origin":null},"content":[{"type":"text","text":"不方便系統維護，經常合併代碼衝突。"}]}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"爲了解決上述問題，將單體服務中的一些功能模塊抽離出來，作爲獨立的服務，逐漸形成穩定的服務中心。服務與服務之間存在遠程調用，多個服務一起完善業務功能"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"例如 用戶服務，交易服務，庫存服務等等，分別由不同團隊維護，並且可以獨自增加機器，方便支持更大的業務量。"}]},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/a1/a1c6deb5c54a5b57e811422f3ba71ee8.png","alt":null,"title":"","style":[{"key":"width","value":"50%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"heading","attrs":{"align":null,"level":5},"content":[{"type":"text","text":"2.3 微服務架構階段"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"當服務越來越多，服務越來越小，服務與服務之間的調用關係。成爲單靠人肉無法理清的關係圖"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"單個服務的如果出現問題，可能引起服務雪崩，拖垮調用方服務"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"新上線的服務如何被調用方即使發現？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"服務的狀態監控？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"等等一系列的問題，等待解決"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"所以這塊提出服務治理的概念，去解決上述提出的一系列問題。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"如果沒有一系列的服務治理基礎設施，所謂的微服務架構階段與RPC架構階段沒有很大區別"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"3. 當下矛盾點"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"（從一個矛盾點切入來探尋問題本質）"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"目前，互聯網微服務架構大行其道，那麼我們需要認識到當前服務的主要矛盾的點所在"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"過去3-5年時期，互聯網處於流量紅利期，那個階段業務野蠻生長，每日的業務量都是一個新的高峯，在那個時期，往往都是不在意成本搶佔市場，機器資源利用率普遍不高。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"隨之互聯網流量紅利期結束，業務野蠻生長的時期也隨之結束。公司開始關心成本，關心服務器的資源利用率"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"但是，提高資源利用率缺不是簡單的縮容，或者代碼優化可以搞定的"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"舉個例子"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"假設你的代碼處於一種完美狀態，最大程度的壓榨的機器性能，但是業務是有高峯低谷時期之分的，例如貓眼電影，重要檔期是業務的最高峯，但是週一到週五業務量其實沒有很大；或者一天中，凌晨1點到凌晨5點基本沒有人購票，晚上8點纔是購票高峯。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"那麼這個時候如何提高資源利用率呢？難道我每天晚上1點縮容，早上6點起來擴容？這不得累死人"}]},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/97/97dc3de7e3c75ca1c1c19b31bd8af2d6.png","alt":null,"title":"","style":[{"key":"width","value":"50%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"4. 解決之道"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"針對當前面臨的矛盾點，有人提出一種解決方案【彈性擴容】【按需計費】"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"啥叫【彈性擴容】【按需計費】"}]},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/ad/ad9366f2f0c8d59a60d20d48c3c29683.png","alt":null,"title":"","style":[{"key":"width","value":"50%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"大白話解釋就是說通過流量，或者機器負載等一些指標判斷是否需要擴容或者縮容，然後服務器的使用成本是按使用時間計費"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"舉個例子"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"貓眼電影，一個服務機器假設有100臺機器。在晚上8點前，發現流量在逐步增加，集羣機器的負載也在逐步增加，資源利用率已經超過60%【彈性擴容】根據這個指標判斷未來是業務上漲階段，就提前擴容了10臺機器，如果過一段時間發現還是集羣機器負載逐步增高，那說明擴容不夠，還要再擴容10臺。等到了凌晨1點，大家都睡覺了，沒有看電影了。發現集羣機器負載降低了好多，流量也降低了好多，資源利用率不到3%【彈性擴容】判斷未來是業務下降階段，那麼就縮容80臺機器。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"這麼做有什麼好處？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"原來沒有【彈性擴容】一天我服務器費用是100 "},{"type":"text","marks":[{"type":"italic"}],"text":" 24 "},{"type":"text","text":" 60 * 60 * M M=每秒鐘的服務使用費。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"現在有【彈性擴容】因爲我業務不同時間段的機器數量不同，業務低峯期的服務器費用基本可以節省80%，那麼服務器的費用將大大降低 。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/84/847a0949aac8b9ecf0c5079273800735.png","alt":null,"title":"","style":[{"key":"width","value":"50%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"5. 問題就解決了？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"看到這裏是不是覺得發現的銀彈，覺得找到了未來之路？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"但是通過【彈性擴容】【按需計費】就把當前問題的矛盾點解決了？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"可以說是，也可以說不是！"}]},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/47/4755576ea4534bb3daf9dc53eff66cbb.png","alt":null,"title":"","style":[{"key":"width","value":"50%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"說解決了，是因爲確實指明解決當前資源利用率不高的問題"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"說沒有解決，說因爲它引出了一個新的問題。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"什麼問題？"},{"type":"text","marks":[{"type":"strong"}],"text":"如何快速拉起一個高性能服務進程"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"什麼是"},{"type":"text","marks":[{"type":"strong"}],"text":"高性能服務進程"},{"type":"text","text":"？"}]},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/13/13199725066ae2bc783fb3aa7a7c038d.png","alt":null,"title":"","style":[{"key":"width","value":"50%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"舉個例子"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"目前一個業務高峯來臨，彈性擴容正在擴容機器，部署服務。但是擴容機器需要申請機器，初始化機器環境等一系列操作，初始化服務器之後，又得重新打包服務代碼，編譯，然後運行。全部執行下來，可能業務高峯期已經到來，流量早已把你的服務擊垮。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"好吧，就算上面這些你都是十分迅速的完成了，假設你服務是一個Java程序，你發佈的服務還未經過JIT即使編譯器的優化，虛擬機解釋執行的效率十分感人，你的服務性能TP99線急劇升高，接口的超時嚴重，引起服務雪崩拖垮調用方服務。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"那如何解決這個問題？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"如何快速拉起一個高性能服務進程"},{"type":"text","text":"？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"這個問題分爲兩個部分解決："},{"type":"text","marks":[{"type":"strong"}],"text":"服務器快速生成，高性能應用快速啓動"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"服務器快速生成"},{"type":"text","text":"的目前解決方案是容器化部署，傳統應用都部署在虛擬機或者物理機器上，相較於前兩者，容器化啓動速度往往遠超前兩者"}]},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/84/841f1ae92e2260e1455f43721df85d06.png","alt":null,"title":"","style":[{"key":"width","value":"75%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"高性能應用快速啓動"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"高性能應用快速啓動也有兩個部分解決"}]},{"type":"numberedlist","attrs":{"start":1,"normalizeStart":1},"content":[{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":1,"number":1,"align":null,"origin":null},"content":[{"type":"text","text":"編譯後做成鏡像包，二次部署無需從服務代碼開始執行編譯，打包等耗時過程"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":1,"number":2,"align":null,"origin":null},"content":[{"type":"text","text":"使用更加輕量級的框架，減少程序包中的代碼數量，並且使用AOT技術，將Java實現編譯成二進制碼，跳過部署完成後，解釋執行的階段"}]}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"第一點還好理解，傳統發佈服務，需要在倉庫中拉Master分支代碼，然後編譯，打包，運行才能啓動起來，如果實現就將打包好程序包做成鏡像，自然可以跳過上述那些十分耗時的時間。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"第二點怎麼理解 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的編程模型和框架開發的程序，存在高內存需求和啓動速度（Class文件需要類加載）緩慢等限制"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"爲了解決上述兩個問題，所以需要一種輕量級的框架去解決。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"目前業界"},{"type":"text","marks":[{"type":"strong"}],"text":"Quarkus"},{"type":"text","text":"開始嶄露頭角，本質上就是一款輕量級框架，並且可以AOT結合直接編譯成二進制碼。可以迅速拉起一個服務，經過測試啓動一個HelloWorld只需要"},{"type":"text","marks":[{"type":"strong"}],"text":"12ms"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"6. 總結"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"上述帶大家瞭解了下當前服務面臨的主要矛盾點，以及業界探索的解決方案。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"當然雲原生要解決的問題絕不是單純上面描述的資源利用率的問題，還有"},{"type":"text","marks":[{"type":"strong"}],"text":"支持業務務快速迭代、業務組合複雜、海量用戶、流量突增、7*24小時高可用，故障轉移，自動恢復"},{"type":"text","text":"等等"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"上面只是從一個點切入給大家講解問題的雲原生的誕生背景"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"至於雲原生的【微服務】【DevOps】【持續交付】【容器化】只是基礎門檻，使用這些並不代表雲原生了，基本上大廠這些基礎設施都是標配。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"所以我們應該清晰認識到雲原生的"},{"type":"text","marks":[{"type":"strong"}],"text":"核心"},{"type":"text","text":"是【按需分配】和【彈性伸縮】"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}}]}