energy

Cloudflare 開始在正式環境用 ARM server 了

在「Designing Edge Servers with Arm CPUs to Deliver 57% More Performance Per Watt」這邊 Cloudflare 提到了他們在正式環境用 ARM 架構了：

Our first Arm CPU was deployed in production earlier this month — July 2021.

記得測了很多年，其中遇到測試到一半看起來還不錯，但原廠商決定不繼續做的，直到後來又有廠商投入，到現在總算是有比較成熟的產品可以用。

隔壁棚 AWS 上的 ARM 伺服器用起來也是香到不行，還沒有用過的可以試看看，至少我這台 blog & wiki 也都是跑在上面。

另外文章裡有提到目前 x86 的效能，新一代的 AMD 大概只比前一代多了 39% 的每瓦效能，但如果是把 ARM 拿進來比的話會到 57%：

Our most recently deployed generation of edge servers, Gen X, used AMD Rome CPUs. Compared with that, the newest Arm based CPUs process an incredible 57% more Internet requests per watt. While AMD has a sequel, Milan (and which Cloudflare will also be deploying), it doesn’t achieve the same degree of energy efficiency that the Arm processor does — managing only 39% more requests per watt than Rome CPUs in our existing fleet.

開始推上 production 後應該會愈換愈快，而且代表 Cloudflare 也會開始針對 ARM 平台最佳化。

挖 Ethereum 加熱房間...

大家都好像有過類似的想法，只是實際去做的不多 XDDD

有人把整個作法寫出來，挖 Ethereum 加熱房間：「How I heat my home by mining crypto currencies」。

從網站上的「About me」這邊看起來應該是住在奧地利？

I am a tech geek from Austin TX (USA), living on the country side in Austria and devote most of my time to my girlfriend, my company, my students and different projects.

不確定是哪個城市，先抓了首都維也納的溫度來看，看起來一到三月的平均氣溫都在個位數 (攝氏)，可以理解暖氣應該是常備物品：

作者之前就先搞過一個可以一路接到 Grafana 的電錶，然後也有裝太陽能電板，但因為暖氣用電的關係而不夠用：

After building my own smart meter using 4$ in parts I started checking my electricity usage every day, which made me realize how expensive it is to heat your home. Especially since all heat and warm water in my low-energy house is made with electricity. I do have 4.8 kwp solar panels on my roof but in winter they don't cover too much for obvious reasons.

順便查了一下電價，在「Austria electricity prices」這頁可以看到奧地利的每一度要 USD$0.248：

而同一份資料上，台灣是 USD$0.101：

回到他的暖氣機，他是屬於中央空調大台機器的類型：

這種機器會恆溫輸出，所以是進風溫度愈低，就需要使用愈高的電能加熱。所以他想到的解法就是針對進風口預先用顯卡挖礦加熱 (四張 AMD 的 R9 390)，這樣就可以降低暖氣機的電力消耗 (不過整體的消耗會提昇)：

I had 4 older AMD R9 390 GPUs laying around (for the nVidia crowd that's basically on a level with a GTX 970) and I thought it could work.

後面就是改裝過程了，最後的結果雖然整體的電力使用量上升，但因為暖氣機的電力消耗降低，加上礦機挖到的 ETH 直接 cover 暖氣機的費用，反而讓暖氣機變免費了：

Success! I was able to lower my heat pump's electricity needs by ~50% and half of the costs are also paid for by the mining earnings

台灣的氣溫應該是用不太到 XDDD

Apple 新的「Find My」帶來的隱私問題

這次 WWDC 推出的新功能，已經有人在討論機制與隱私問題了：「How does Apple (privately) find your offline devices?」。

前一代的「Find my iPhone」需要透過網路與 GPS 資料才能在系統上看到，這一代則是加上 BLE beacon，然後任何一台 iOS device 收到後就回傳回給蘋果：

Every active iPhone will continuously monitor for BLE beacon messages that might be coming from a lost device. When it picks up one of these signals, the participating phone tags the data with its own current GPS location; then it sends the whole package up to Apple’s servers.

幾個隱私問題在於，代傳的 iOS device 也會暴露位置資訊給蘋果，另外收到 BLE beacon 的 iOS device 本身是否可以解讀遺失機器的資訊？而商家看起來也可以利用這個方式主動發送攻擊而得知不少資料 (像是文章裡提到先前蘋果透過 randomize mac address 加強隱私的問題，這邊又多開了一個洞)，現在蘋果給的資訊還不夠清楚，需要真的逆向工程確認才知道...

加州打算強制規定新房子都要有太陽能...

加州打算直接從法律上規定從 2020 年開始的新房子都要有太陽能：「California set to become first US state requiring solar panels on new homes」。

The state’s Energy Commission is due to vote next week on new energy standards that would require virtually all new homes to be constructed with solar panels from 2020.

如果通過的話，從 20% 直接變成強制性的 100%：

Currently around 20 per cent of single-family homes are constructed with solar capacity built in, but if the new standards are approved as expected this proportion will rise sharply.

下個禮拜回來看看消息好了，這應該是蠻指標性的事情... 無論是在經濟上還是在環保題材上。

舊金山要求新的建築物都必須有太陽能設備

舊金山通過在 2017 年之後的建築物必須有 15% 的屋頂面積必須是太陽能相關的設備：「San Francisco Is Requiring Solar Panels on All New Buildings」：

The ordinance, passed unanimously by the city’s Board of Supervisors, extends an existing California law which requires 15 percent of roof space on new buildings to be “solar ready” — available and unshaded. That ordinance applies to residential or commercial buildings 10 stories or shorter.

也就是說，可以是太陽能的發電，也可以是太陽能集熱的設備：

Under the new ordinance, which will go into effect in 2017, new buildings need to have solar energy of some kind installed, either electricity-generating panels or solar heating units.

希望在 2020 年達到 100% 再生能源的目標：

San Francisco took a major step toward its own goal of meeting the city’s electricity demands with 100 percent renewable energy by 2020.

這成為美國第一個主要城市通過這樣的規範：

This week, San Francisco became the first major U.S. city to require all new buildings to have solar panels on their roofs, according to Scott Wiener, the city supervisor who introduced the bill.