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寄硬碟的 AWS Snowball 與 AWS Snowball Edge 支援東京了

AWS SnowballAWS Snowball Edge 這兩個服務實際上就是透過硬碟寄送加速資料傳遞,只是做了很多保護 (物理面與資料安全面)。

而這兩個服務宣佈在東京區開放了 (ap-northeast-1,包括 AWS Snowball 與 AWS Snowball Edge):「AWS Snowball and AWS Snowball Edge Available in Asia Pacific (Tokyo) Region」。

這樣對於需要倒入 (以及倒出) 大量資料的服務又簡化了不少... (以往要從其他地區想辦法,而且還會遇到不支援寄來台灣的問題)

Netflix 對 sendfile() 在 TLS 情況下的加速

Netflix 對於寫了一篇關於隱私保護的技術細節:「Protecting Netflix Viewing Privacy at Scale」。

其中講到 2012 年的 Netflix Open Connect 中的 Open Connect Appliance (OCA,放伺服器到 ISP 機房的計畫) 只有單台伺服器 8Gbps,到現在 2016 可以達到 90Gbps:

As we mentioned in a recent company blog post, since the beginning of the Open Connect program we have significantly increased the efficiency of our OCAs - from delivering 8 Gbps of throughput from a single server in 2012 to over 90 Gbps from a single server in 2016.

早期的 Netflix 走 sendfile() 將影片丟出去,這在 kernel space 處理,所以很有效率:

當影片本身改走 HTTPS (TLS) 時,其中一個遇到的效能問題是導致 sendfile() 無法使用,而必須在 userland space 加密後改走回傳統的 write() 架構,這對於效能影響很大:

所以他們就讓 kernel 支援 AES 系列加密 (包括 AES-GCM 與 AES-CBC),效能的提昇大約是 30%:

Our changes in both the BoringSSL and ISA-L test situations significantly increased both CPU utilization and bandwidth over baseline - increasing performance by up to 30%, depending on the OCA hardware version.

文章開頭也有提到選 AES-GCM 與 AES-CBC 的一些來龍去脈,主要是 AES-GCM 的安全強度比較好,另外考慮到舊的 client 不支援 AES-GCM 時會使用 AES-CBC:

We evaluated available and applicable ciphers and decided to primarily use the Advanced Encryption Standard (AES) cipher in Galois/Counter Mode (GCM), available starting in TLS 1.2. We chose AES-CGM over the Cipher Block Chaining (CBC) method, which comes at a higher computational cost. The AES-GCM cipher algorithm encrypts and authenticates the message simultaneously - as opposed to AES-CBC, which requires an additional pass over the data to generate keyed-hash message authentication code (HMAC). CBC can still be used as a fallback for clients that cannot support the preferred method.

另外 OCA 機器本身也都夠新,支援 AES-NI 指令集,效能上不是太大的問題:

All revisions of Open Connect Appliances also have Intel CPUs that support AES-NI, the extension to the x86 instruction set designed to improve encryption and decryption performance. We needed to determine the best implementation of AES-GCM with the AES-NI instruction set, so we investigated alternatives to OpenSSL, including BoringSSL and the Intel Intelligent Storage Acceleration Library (ISA-L).

不過在「Netflix Open Connect Appliance Deployment Guide」(26 July 2016 版) 這份文件裡看起來還是用多條 10Gbps 透過 LACP 接上去:

You must be able to provision 2-4 x 10 Gbps ethernet ports in a LACP LAG per OCA. The exact quantity depends on the OCA type.

可能是下一版準備要上 40Gbps 或 100Gbps 的準備...?

AWS 推出備份用的硬體設備:Snowball

AWS Import/Export 服務推出硬體:「AWS Import/Export Snowball – Transfer 1 Petabyte Per Week Using Amazon-Owned Storage Appliances」。

原先 AWS Import/Export 需要自己買硬碟寄到 AWS 指定的地方,對於一次性的用途來說不太合理 (硬碟只用一次?),而現在 AWS Import/Export 推出整台 appliance 來解決這個問題,長這樣:

本身就是可郵寄的包裝,包括了 E-ink 電子墨水面板 (很明顯是從 Kindle 那邊弄來的技術),所以連寄回的地址都不用填寫。而本身就有防水防震設計保護寄送過程稍微摔到或是淋到水也不會有事情,另外透過 AES 256bits 安全加密確保資料不會被盜用,NIST Special Publication 800-88 確認加密的資料沒有被盜取。


而每個 appliance 可以傳輸 50TB 的資料:

From there you simply copy up to 50 terabytes of data to the Snowball and disconnect it (a shipping label will automatically appear on the E Ink display), and ship it back to us for ingestion.

目前支援美東 (us-east-1) 與美西二區 (us-west-2):

You can import data to the US Standard and US West (Oregon) regions, with more on the way.