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Facebook 自己找人研究,Social Media 是否對人類有害 XDDD

之前看到「Hard Questions: Is Spending Time on Social Media Bad for Us?」這篇,一直不知道要怎麼吐槽... 然後看到 Twitter 上的這則 tweet XDDD

既視感太重了,找了一下其他行業對應的資料:

真的不知道怎麼吐槽 XDDD

CPU 成為現代網站的速度瓶頸

在「Tracking CPU with Long Tasks API」這邊提到的現象,雖然是在提新的 API,不過裡面提到了很重要的問題。

以前的網站因為 js 都沒有用的那麼多,所以主要的瓶頸在於網路速度。所以大家最佳化的方向都是往「如何讓傳輸量變小」的方式進行,像是各類 js 的 minify,甚至是對 Gzip 演算法的暴力改善 (維持相容的 Zopfli,以及新的 Brotli):

In the old days, delivering a fast user experience depended primarily on download speed. One reason why the network was the main bottleneck back then is that JavaScript and CSS weren’t used as much as they are now, so CPU wasn’t a critical factor.

而現代網站使用 js 的情況已經是來到了新的境界 (甚至很多網站是沒有 js 就不會動),於是對於 CPU 的能力就愈來愈要求:

According to the HTTP Archive, the top 1000 websites download five times more JavaScript today compared to seven years ago.

而手機也愈來愈普及,CPU 的能力相較起來就更嚴峻了...

Google 發表新的 TTS (Text-to-Speech) 技術 Tacotron 2

Tacotron 是 Google 發表的 TTS 技術 (i.e. 輸入文字,請電腦發音),而前一版的 Tacotron 的錄音可以參考「Audio samples from "Tacotron: Towards End-to-End Speech Synthesis"」,論文則是在「Tacotron: Towards End-to-End Speech Synthesis」這邊可以看到。

這一版的則是在 Twitter 上看到有人提到:

這一版叫做 Tacotron 2,錄音可以參考「Audio samples from "Natural TTS Synthesis by Conditioning WaveNet on Mel Spectrogram Predictions"」,論文在「Natural TTS Synthesis by Conditioning WaveNet on Mel Spectrogram Predictions」。

這次在錄音頁面的最下面提供了盲測 (人類與 Tacotron 2 的錄音),基本上已經分不出哪個是真人了...

Amazon API Gateway 支援壓縮了...

Amazon API Gateway 支援壓縮了:「Amazon API Gateway Supports Content Encoding for API Responses」。

You can now enable content encoding support for API Responses in Amazon API Gateway. Content encoding allows API clients to request content to be compressed before being sent back in the response to an API request. This reduces the amount of data that is sent from API Gateway to API clients and decreases the time it takes to transfer the data. You can enable content encoding in the API definition. You can also set the minimum response size that triggers compression. By default, APIs do not have content encoding support enabled.

打開後傳回的資料就會自動壓縮了,然後還可以設定觸發的 response size... 依照文件 (Content Codings Supported by API Gateway),目前支援的壓縮格式應該是最常見的 gzipdeflate

這功能好像是一開始有 API Gateway 就一直被提出來的 feature request...

Amazon Elasticsearch 支援 I3 instance (i.e. 1.5 PB Disk) 了

Amazon Elasticsearch 支援 I3 instance 了:「Run Petabyte-Scale Clusters on Amazon Elasticsearch Service Using I3 instances」。

Amazon Elasticsearch Service now supports I3 instances, allowing you to store up to 1.5 petabytes of data in a single Elasticsearch cluster for large log analytics workloads.

i3.16xlarge 單台是 15.2 TB 的硬碟空間,100 台就會是 1.5 PB,不知道跑起來會多慢 XDDD

Amazon Elasticsearch Service – Amazon Web Services (AWS) | FAQs 這邊還沒修正 XD:

You can request a service limit increase up to 100 instances per domain by creating a case with the AWS Support Center. With 100 instances, you can allocate about 150 TB of EBS storage to a single domain.

新出的 RFC 8259:The JavaScript Object Notation (JSON) Data Interchange Format

JSON 的規格書又被更新了 XD

在「The Last JSON Spec」這邊,Tim Bray 寫了這篇關於新的 RFC 8259 跟之前的差異,以及大家對於雙重標準的顧慮。

最大的差異在於,在 RFC 8259 規定了「如果 JSON 被用在非封閉的系統交換資料,必須使用 UTF-8」:

8259 con­tains one new sen­tence: “JSON text ex­changed be­tween sys­tems that are not part of a closed ecosys­tem MUST be en­cod­ed us­ing UTF-8 [RFC3629].” Giv­en that, by 2017, an at­tempt to ex­change JSON en­cod­ed in any­thing but UTF-8 would be ir­ra­tional, this hard­ly needs say­ing; but its ab­sence felt like an omis­sion.

而關於 ECMA-404 與 RFC 8259 都定義了 JSON 的問題他也說明了,因為很多人花了很多力氣在確保這兩份文件的正確性上,所以應該不會有問題 (i.e. 衝突):

The rea­son 8259 ex­ists is that the ECMAScript gang went and wrote their own ex­treme­ly min­i­mal spec, Stan­dard ECMA-404: The JSON Da­ta In­ter­change Syn­tax, and there was rea­son for con­cern over du­el­ing stan­dard­s. But, af­ter a cer­tain amount of standards-org elephant-gavotte, each of ECMA 404 and RFC 8259 nor­ma­tive­ly ref­er­ences the oth­er and con­tains a com­mit­ment to keep them con­sis­tent in case any er­rors turn up. Which is a good thing, but this text has been re-examined and re-polished so many times that I doubt ei­ther side will ev­er re­vis­it the ter­ri­to­ry, thank good­ness.

另外他也提到了對於不同情境下可以看不同的文件。像是要了解 JSON 的話,可以看當初發明 JSON 的 Doug Crockford 所設立的網站 (在「JSON」這邊);而在交換時應該參考 I-JSON (Internet JSON,RFC 7493):

Which spec should you use? · If you want to un­der­stand JSON syn­tax, you still can’t beat Doug Crockford’s orig­i­nal for­mu­la­tion at JSON.org. If you want to use an RFC as foun­da­tion for a REST API or some oth­er In­ter­net pro­to­col, I ac­tu­al­ly don’t rec­om­mend 8259, I rec­om­mend I-JSON, RFC 7493, which de­scribes ex­act­ly the same syn­tax as all the oth­er specs (by ref­er­enc­ing 7159), but ex­plic­it­ly rules out some legal-but-dumbass things you could do that might break your pro­to­col, for ex­am­ple us­ing any­thing but UTF-8 or hav­ing du­pli­cate mem­ber names in your ob­ject­s.

I-JSON 是 JSON 的子集合,比較重要的:

  • (MUST) 使用 UTF-8。
  • (SHOULD NOT) 浮點數的部份,不得超過 IEEE 754-2008 binary64 (double precision) 的範圍。
  • (SHOULD NOT) 整數的部份,不得超過 [-(2**53)+1, (2**53)-1]) 的範圍。
  • (RECOMMEND) 有超過的需求使用字串表示。
  • (MUST NOT) JSON object 內不得有重複的 name。
  • (SHOULD NOT) 最上層的型態不得使用字串,只能使用 object 或是 array。
  • (MUST NOT) 遇到先前沒有定義過的元素不得視為錯誤。(像是新版 API 內會在 object 裡增加元素)
  • (RECOMMEND) 時間使用 ISO 8601 表示 (在 RFC 3339 有提到),英文字的部份全部使用大寫,一定要標上時區,而秒數的 0 一定要加上去 (也就是 00 秒)。
  • (RECOMMEND) 時間長度也建議依照 RFC 3339 處理。
  • (RECOMMEND) Binary 資料用 base64url 傳 (RFC 4648)。

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