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AWS 接受不同的幣別付款

剛剛看到 AWS 宣佈接受不同幣別的付款:「New – Set Preferred Payment Currency for your AWS Account」。

當你使用 Visa 或是 MasterCard 時,除了美金外,目前支援這些幣別:

  • Australian Dollars (AUD)
  • Swiss Francs (CHF)
  • Danish Kroner (DKK)
  • Euros (EUR)
  • British Pounds (GBP)
  • Hong Kong Dollars (HKD)
  • Japanese Yen (JPY)
  • Norwegian Kroner (NOK)
  • New Zealand Dollars (NZD)
  • Swedish Kronor (SEK)
  • South African Rand (ZAR)


用 Go 寫的 Tor Relay Server

Zite 上看到的「Implementing a Tor relay from scratch」,用 Go 寫的 Tor Relay Server。

會跳下去用 Go 寫是因為效能上的考量:

[...], but the lack of AES-NI instructions on the CPUs cause a significant slowdown.

但因為一個 IP 只能跑兩個 instance,這就有點痛了:

To maximize the amount of relayed data, it is normal to simply run multiple instances of the program, up to two per IP address.


My final goal was to beat the Tor speed record, which was at roughly 200 megabytes per second.

成果就是直接吃滿 2Gbps (250MBytes/sec),而且 CPU 只用了 60%:

[...] He set up a server with my relay and within a few days we had broken the Tor speed record with a nice 250 megabytes per second, effectively maxing out the network link. CPU usage was at a nice 60% across 12 cores. But his relay also suffered from the memory issues and had to be restarted every few days.

作者的程式碼放在 GitHub 上,之後應該會有人跳進去改寫:「A fast implementation of the Tor OR code, in Go」。

Mozilla 的 Shumway 登陸 Firefox Nightly Channel

MozillaShumway 專案是用 JavaScript 實作的 Flash Player,算是把 Flash Plugin 淘汰掉的方案:

Shumway is an HTML5 technology experiment that explores building a faithful and efficient renderer for the SWF file format without native code assistance.

由於是跑在 JavaScript 內,安全性受到 SpiderMonkey 的 Sandbox 保護,相較於 Adobe 常常出 security update 讓人有點頭痛...

最近 Shumway 的大進展是在 Firefox Nightly Channel 啟用了部份網站,可以測試 Amazon.com 上的影片:「Firefox Nightly now plays Amazon.com Flash videos using Shumway」。

不知道有沒有機會 porting 到 Google Chrome 上面...

Open Source 版本的「不重開機更新 Linux Kernel」,kSplice 的替代方案

一般的 Linux Kernel 更新需要重開機,其中有個商用方案 kSplice 可以做到這點,不過這需要付錢給 Oracle

Slashdot 上看到 Live Patching 功能的 Open Source 方案前進了一大步:「Live Patching Now Available For Linux」,對應的 Git 記錄在「Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching」這邊。

RedHatSUSE 都各自實做了對應的版本,而這次 Linus 是在 Kernel 內引入對應的 API,讓 Userland 的程式可以實現對應的功能:

It provides a basic infrastructure for function "live patching" (i.e. code redirection), including API for kernel modules containing the actual patches, and API/ABI for userspace to be able to operate on the patches (look up what patches are applied, enable/disable them, etc).

可以馬上想到的是,之後更新 MySQL 就不用重熱 InnoDB 的 data 了,來繼續關注進展...