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Amazon EC2 推出 4TB 的機器

之前 Amazon EC2 記憶體最大的機器是 x1.32xlarge 的 2TB RAM (更精確是 1952GB),現在推出了 4TB RAM 的 x1e.32xlarge (3904GB):「Now Available – EC2 Instances with 4 TB of Memory」。

現在這個時間點在 us-east-1 的價錢是 USD$26.688/hour (一個月 USD$19215.36),用的到的人應該付得起?

另外值得注意的是,x1e.32xlarge 雖然比 x1.32xlarge 多了一倍的記憶體,但 vCPU 不變 (都是 128),而且 ECU 下降了 (從 349 降到 340)。

這個機器目前在 us-east-1us-west-2eu-west-1ap-northeast-1 四區提供服務:

The x1e.32xlarge instances can be launched in On-Demand and Reserved Instance form via the AWS Management Console, AWS Command Line Interface (CLI), AWS SDKs, and AWS Marketplace in the US East (Northern Virginia), US West (Oregon), EU (Ireland), and Asia Pacific (Tokyo) Regions.

Mozilla 的提案「HTTP Immutable Responses」

狀態已經是 Category: Standards Track 了,RFC 8246 的「HTTP Immutable Responses」:

The immutable HTTP response Cache-Control extension allows servers to identify resources that will not be updated during their freshness lifetime. This ensures that a client never needs to revalidate a cached fresh resource to be certain it has not been modified.

Cache-Control 介紹了 immutable,像是這樣:

Cache-Control: max-age=31536000, immutable

依照 MDN 上的資料 (Cache-Control - HTTP | MDN),目前只有 EdgeFirefox 支援,不過既然成為標準了,後續其他瀏覽器應該都會支援 (吧):

GitHub Debug

GitHub 推出工具讓使用者可以方便回報狀態:「GitHub Debug」。

做起來不困難,但等於是讓使用者操作 SOP 先提供一些基本的資訊,讓 GitHub 內部的人在處理時會比較輕鬆。

EC2 的 Spot Instance 可以「接關」

Amazon EC2Spot Instance 可以「接關」了:「New – Stop & Resume Workloads on EC2 Spot Instances」。

當 Spot Instance 的競價不足以標到機器時,他會先關起來 (Stop),等到價錢低於競價後就會再打開機器,這時候的狀態就會恢復。另外也提到了必須是使用 EBS 的機器才支援:

Amazon EC2 Spot now allows Amazon EBS-backed instances to be stopped in the event of interruption, instead of being terminated when capacity is no longer available at your preferred price. Spot can then fulfill your request by restarting instances from a stopped state when capacity is available within your price and time requirements.

用法是把 Spot Instance 的關機設定設為 Stop:

To use this new feature, choose “stop” instead of “terminate” as the interruption behavior when submitting a persistent Spot request. When you choose “stop”, Spot will shut down your instance upon interruption.

恢復的時候就會儘量保持一樣地開回來 (連 instance id 都相同):

When capacity is available again within your price and time requirements, Spot will restart your instance. Upon restart, the EBS root device is restored from its prior state, previously attached data volumes are reattached, and the instance retains its instance ID.

是個接關的感覺 XD

HHVM 的後續

官方對於 HHVM 的未來提出了說明:「The Future of HHVM」。重點就是他們不打算以 PHP7 為目標,打算關起來自己玩...:

Consequently, HHVM will not aim to target PHP7. The HHVM team believes that we have a clear path toward making Hack a fantastic language for web development, untethered from its PHP origins.

如果以 Packagist 上的資料來看 (PHP Versions Stats - 2017.1 Edition),HHVM 的數量應該是沒人了:

And because a few people have asked me this recently, while HHVM usage is not included above in the graph it is at 0.36% which is a third of PHP 5.3 usage and really hardly significant. I personally think it's fine to support it still in libraries if it just works, or if the fixes involved are minor. If not then it's probably not worth the time investment.

Comment 的地方有註明這是扣掉 CI 的量:

@ocramius: These numbers ignore Travis CI and other CI systems that set the "CI" env var in their workers. Without excluding those HHVM is around 0.95% so it's still low but those .36% is probably actual usage.

這樣就放心可以完全不用管 HHVM 了 XDDD

GitHub 明年關閉 SSH 上 SHA1 相關的 Kx (Key Exchange) 演算法

GitHub 定下落日條款了:「Weak cryptographic standards deprecation update」。

這次目標是 diffie-hellman-group1-sha1diffie-hellman-group14-sha1,同時啟用了 diffie-hellman-group-exchange-sha256

Since the announcement, we have been focusing on the impact of disabling the diffie-hellman-group1-sha1 and diffie-hellman-group14-sha1 key exchanges for SSH. As of last week, we have enabled diffie-hellman-group-exchange-sha256. This key exchange method is widely supported and will allow most legacy clients to seamlessly transition away from diffie-hellman-group1-sha1 and diffie-hellman-group14-sha1.

明年二月拔掉 diffie-hellman-group1-sha1diffie-hellman-group14-sha1

This is a very small percentage of traffic, but we would like to see if we can reduce the incompatible traffic percentage even further before disabling support for the older key exchange algorithms on February 1, 2018.

EC2 與 EBS 十月開始以秒計費

雖然只是 Amazon EC2Amazon EBS 計價模式的改變,但這次 AWS 的改變對於許多開發流程有很大的影響 (重點在 EC2 的部份):「New – Per-Second Billing for EC2 Instances and EBS Volumes」。

10/2 開始改變 (而不是 10/1),低消一分鐘,Windows 機種以及需要額外收費的 Linux 機種不在範圍內:

This change is effective in all AWS Regions and will be effective October 2, for all Linux instances that are newly launched or already running. Per-second billing is not currently applicable to instances running Microsoft Windows or Linux distributions that have a separate hourly charge. There is a 1 minute minimum charge per-instance.

然後 Spot 與買 RI 後也是一樣以秒計價:

List prices and Spot Market prices are still listed on a per-hour basis, but bills are calculated down to the second, as is Reserved Instance usage (you can launch, use, and terminate multiple instances within an hour and get the Reserved Instance Benefit for all of the instances).

這次改變的影響很巨大。馬上可以想到幾個情境...

第一個是對於實踐 Release early, release often 的團隊來說,如果設計成每 deploy 一次就建一個新的 AMI (最乾淨的作法),再開新機器換掉的話,成本就會增加不少。所以對於這樣的團隊,就會偏好朝著替換現有目錄內的東西後重啟...

現在改成以秒計費後,直接透過 Blue-Green Deployment 就可以了 (AWS CodeDeploy 年初也支援了:「AWS CodeDeploy 支援 BlueGreenDeployment」):(如果不熟悉 Blue-Green Deployment 的話,更白話的說法就是「先建後拆」...)

同樣的理由,對於 Auto Scaling 的 policy 也有些改變。之前機器開起來都會想讓他跑一個小時,所以 scale down 的部份都會寫的比較鬆一點。現在就可以重新規劃了...

另外一個影響是對使用 container 的誘因少了不少。很多人用 container 的用法是開大台機器再裡面拆給不同服務用,讓資源利用率變高,現在變成用多少算多少後就不太需要這樣了...

當然也還是有缺點。以前 Spot Instance 如果被 AWS 收回時,最後的那個小時是不計費的。現在因為以秒計費,變成要收費了...

最後是 10/2 生效這件事情頗怪,該不會是財務部門不願意配合 10/1 星期天加班生效,所以只好變成 10/2 生效這種理由吧... XDDD

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