Mac 會自己改變 Desktop 位置的問題

以前好像沒遇過,換了 M1 以後才注意到 desktop 位置位自己被改變,覺得很阿雜... 找了資料才發現是個 "feature":「How to prevent Mac from changing the order of Desktops/Spaces」。

關掉就好了,網路上的資料最早出現在 2018 年左右,大概是那個時候被加進去的?

Apple 使用 Cassandra 的量

Hacker News Daily 上看到的:「Cassandra at Apple: 1000s of Clusters, 300k Nodes, 100 PB (twitter.com/erickramirezau)。原文在 Twitter 上:

有些數字有點對不太起來,裡面提到 300K nodes + millions of QPS,但通常讀寫都算 QPS,這樣聽起來很少?所以有種可能這邊是只有算 read 的部份...

另外照片裡面提到 Over two petabytes per cluster,但有 thousands of clusters,最後卻只有 Hundreds of petabytes of data,完全對不上,就算當作平均值來算也對不上,只能猜測是最大的 cluster 而不是 per cluster。

裡面矛盾的地方太多,所以這些數字基本上沒有參考價值,現在能讀出來的只知道 Apple 有在用 Cassandra,然後不是少少幾台 PoC 等級的使用。

歐盟 2024 年年底強制使用 USB-C 充電頭 (終於,iPhone...)

Hacker News Daily 上看到「EU Passes Law to Switch iPhone to USB-C by End of 2024」,裡面指到了歐盟的新聞稿:「Long-awaited common charger for mobile devices will be a reality in 2024」。

2024 年年底 (所以是 2025 年) 將強制手機與平板都使用 USB-C 充電頭,2026 年則是延伸涵蓋到筆電:

By the end of 2024, all mobile phones, tablets and cameras sold in the EU will have to be equipped with a USB Type-C charging port. From spring 2026, the obligation will extend to laptops.

終於定案公告了,之前傳言好久了...

Apple M1 上跑 Linux 的 GPU driver 會動了

Hacker News Daily 上看到「Native Linux GPU Driver for Apple M1 (twitter.com/linaasahi)」這個,講 Apple M1 上有 Linux GPU driver 可以用了,原文是 Twitter 上的推:

不過從 YouTube 的影片上可以看到就只是「會動」,還有不少 rendering bug,可以看到有時候會破格,但畢竟是開始支援了,後續如果有修到穩定的話,直接的好處應該就是把瀏覽器的 rendering 丟給 GPU 處理,就像 macOS 或是 Windows 上的情況。

iOS 12.5.6

早上發現 iPhone 6 Plus 被自動更新到 iOS 12.5.6,查了一下發現是八月底的時候 Apple 推了一版 WebKitACECVE-2022-32893:「About the security content of iOS 12.5.6」。

Impact: Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited.

Description: An out-of-bounds write issue was addressed with improved bounds checking.

上個更新的版本 12.5.5 是 2021/09/23 出的,本來大家都以為已經沒有任何更新了,沒想到居然回過頭來發了一包,照蘋果的敘述看起來是因為這個洞被廣泛使用的關係?

iPhone 5S (目前 iOS 12 支援列表裡最早出的手機) 是 2013 下半年出的,到現在也九年了...

iOS Safari 擋 "Open in App" 的付費套件 Banish

在「New iOS App Blocks Those Annoying 'Open in App' Pop-Ups in Safari」這邊看到 John Gruber 的介紹文章「Banish: New Safari Extension to Block 'Open in App' Dickpanels」,裡面提到的 extension 在「Banish for Safari」這邊,一次性的費用,在台灣是 NT$70。

裡面的 screenshot 給了還蠻清楚的說明:

設定上面因為會牽扯到 privacy 的關係,會有點麻煩,需要開好幾個地方。

順道一提,桌面上的話可以透過 Annoyances 系列的 list 在 uBlock Origin 上擋。

Amazon EC2 有 Mac (M1) 機種可以租用了

2020 年年底的時候 AWS 推出用 Mac mini 配合搭建出 Mac (Intel) 機種:「Amazon EC2 推出 Mac Instance」,當初有計畫在 2021 年推出 M1 的版本:

Apple M1 Chip – EC2 Mac instances with the Apple M1 chip are already in the works, and planned for 2021.

不過就沒什麼意外的 delay 了,這次則是推出了 M1 的版本:「New – Amazon EC2 M1 Mac Instances」。

依照說明看起來還是 Mac mini,掛上 AWS Nitro System

EC2 Mac instances are dedicated Mac mini computers attached through Thunderbolt to the AWS Nitro System, which lets the Mac mini appear and behave like another EC2 instance.

然後跟 Intel 版本一樣,因為是掛進 Dedicated Hosts 的計價方式,雖然是以秒計費,但還是設定最低 24 小時的租用時間限制:

Amazon EC2 Mac instances are available as Dedicated Hosts through both On Demand and Savings Plans pricing models. The Dedicated Host is the unit of billing for EC2 Mac instances. Billing is per second, with a 24-hour minimum allocation period for the Dedicated Host to comply with the Apple macOS Software License Agreement. At the end of the 24-hour minimum allocation period, the host can be released at any time with no further commitment.

Intel 版本代號是 mac1,只有一種機種 mac1.metal,M1 版本代號是 mac2,也只有一種機種 mac2.metal

以最經典的美東一區 us-east-1 來看,mac1.metal 的 on-demand 價錢是 US$1.083/hour,mac2.metal 則是 US$0.65/hour,差不多是 60% 的價錢,便宜不少,大概是反應在硬體攤提與電費成本上了。

另外目前大家用 M1 的經驗來看,Rostta 2 未必會比原生的機器慢多少,雖然 mac1.metal 是 12 cores,mac2.metal 是 8 core,但以雲上面一定要用 Mac 跑的應用來說,馬上想的到的還是綁在 Apple 環境裡 CI 類的應用?

目前看起來主要的問題還是 24 小時的最小計費單位讓彈性低不少...

Apple 在 iOS 16、iPadOS 16 與 macOS Ventura 上推出 Lockdown Mode

AppleiOS 16、iPadOS 16 與 macOS Ventura 上推出了 Lockdown Mode:「Apple expands industry-leading commitment to protect users from highly targeted mercenary spyware」。

Lockdown Mode 主要是透過降低被攻擊的面積以提昇安全性,依照 Apple 的預想,主要是針對被政府單位盯上的族群:

Apple is previewing a groundbreaking security capability that offers specialized additional protection to users who may be at risk of highly targeted cyberattacks from private companies developing state-sponsored mercenary spyware.

在 Lockdown Mode 下目前列出來的限制:

  • Messages: Most message attachment types other than images are blocked. Some features, like link previews, are disabled.
  • Web browsing: Certain complex web technologies, like just-in-time (JIT) JavaScript compilation, are disabled unless the user excludes a trusted site from Lockdown Mode.
  • Apple services: Incoming invitations and service requests, including FaceTime calls, are blocked if the user has not previously sent the initiator a call or request.
  • Wired connections with a computer or accessory are blocked when iPhone is locked.
  • Configuration profiles cannot be installed, and the device cannot enroll into mobile device management (MDM), while Lockdown Mode is turned on.

列出來的這些的確都是之前 0-day 常被拿來打的東西,把攻擊面積縮小的確會有不少幫助。

這應該是業界第一個大咖跳進來做這個 (也就兩個大咖?),第一次搞未必會完美,但算是個開始,後面應該會有更多的面積被考慮進去...

歐盟通過 Digital Markets Act 與 Digital Services Act

Hacker News Daily 上翻的時候看到的大消息,歐盟通過了 Digital Markets Act (DMA) 與 Digital Services Act (DSA):「EU Approves Landmark Legislation to Regulate Apple and Other Big Tech Firms」,這兩個法案會直接衝擊大企業壟斷的情況。

找了一下中文的資料,iThome 有報導:「歐洲議會通過《數位服務法》與《數位市場法》!傳訊服務必須互通,不得禁止使用者採用第三方App Store」。

其中 MacRumors 上的文章整理的蠻清楚的,DMA 包括了:

  • Allow users to install apps from third-party app stores and sideload directly from the internet.
  • Allow developers to offer third-party payment systems in apps and promote offers outside the gatekeeper's platforms.
  • Allow developers to integrate their apps and digital services directly with those belonging to a gatekeeper. This includes making messaging, voice-calling, and video-calling services interoperable with third-party services upon request.
  • Give developers access to any hardware feature, such as "near-field communication technology, secure elements and processors, authentication mechanisms, and the software used to control those technologies."
  • Ensure that all apps are uninstallable and give users the ability to unsubscribe from core platform services under similar conditions to subscription.
  • Give users the option to change the default voice assistant to a third-party option.
  • Share data and metrics with developers and competitors, including marketing and advertising performance data.
  • Set up an independent "compliance function" group to monitor its compliance with EU legislation with an independent senior manager and sufficient authority, resources, and access to management.
  • Inform the European Commission of their mergers and acquisitions.

可以看出來除了最後兩項是針對 EU 的監管機制外,其他的包括了安裝來自第三方的軟體、可以使用第三方的付款系統、可以整合系統服務、可以整合硬體功能、可以使用第三方的語音工具、可以反安裝所有的 app 以及提供平台蒐集到的資料給開發者,都是針對現在 AppleApp StoreGoogle Play 所限制的條件。

另外 DMA 也禁止了這些行為:

  • Pre-install certain software applications and require users to use any important default software services such as web browsers.
  • Require app developers to use certain services or frameworks, including browser engines, payment systems, and identity providers, to be listed in app stores.
  • Give their own products, apps, or services preferential treatment or rank them higher than those of others.
  • Reuse private data collected during a service for the purposes of another service.
  • Establish unfair conditions for business users.

而 DSA 的部份則是針對網路上的非法內容處理:

The Digital Services Act (DSA), which requires platforms to do more to police the internet for illegal content, has also been approved by the European Parliament.

其中 DMA 的生效日看起來會在 2023 年年中生效?應該是 六個月加上六個月...

Once formally adopted, the Act, which takes the legal form of a Regulation, will enter into force 20 days after publication in the EU Official Journal and will apply six months later. The designated gatekeepers will have a maximum of six months after the designation decision by the Commission to ensure compliance with the obligations laid down in the Digital Markets Act.

而 DSA 至少要到 2024 年才有機會會實施:

Once adopted, the DSA will be directly applicable across the EU and will apply fifteen months or from 1 January 2024, whichever later, after entry into force.

歐盟的市場夠大,這個應該會帶來足夠大的衝擊...

Mac 上 sprintf 的 scalability 問題

Hacker News 上看到個有趣的 scalability 問題,在 Mac 上的 sprintf() 因為有 lock 造成的 scalability 問題:「Curious lack of sprintf scaling (aras-p.info)」。

作者注意到 Mac 在多 CPU 下 sprintf() 會有 scalability 的問題,要注意到這邊的 Y 軸是對數比例:

用了 std::stringstream << 反而更慢 (作者還酸了一句「Zero cost abstractions」):

然後用了 Instruments 跑 profiling 找問題,可以看到看起來跟 locale 有關:

一般的情況下應該不會是問題,但如果是需要大量 sprintf() 組字串的人就會比較要注意了。

在「What else can we do?」這段有提到一些解法,包括了 stb_sprintf 當作替代品,以及 {fmt} 作為 iostreams 的替代品,然後另外是利用 to_chars 來解決,如果只是要把數字轉成字串。

算是蠻有趣的 bug hunting 過程,對於開發者來說,一般性的重點還是在 profiling,找到對的問題然後再往下提出解法...