March 2015 – Gea-Suan Lin's BLOG

Amazon EC2 推出 D2 instance (超大硬碟空間)

在「The Next Generation of Dense-storage Instances for EC2」這邊公佈了 Amazon EC2 新的 D2 instance：

最大台有 48TB 硬碟與 244GB 記憶體，這規格好熟悉...

然後這次是全地區一起上，不過看起來不包括美國政府用的 AWS GovCloud (US)：

You can launch d2 instances today in the US East (Northern Virginia), US West (Oregon), Europe (Ireland), Europe (Frankfurt), Asia Pacific (Tokyo), Asia Pacific (Singapore), and Asia Pacific (Sydney) regions as On-Demand, Reserved Instances, or Spot Instances.

RSA Conference 2015 禁止 Show Girl

前幾天的消息：「RSA Conference Bans "Booth Babes"」。報導出自於「RSA Conference bans ‘booth babes’」。

規範的文字：

All Expo staff are expected to dress in business and/or business casual attire. Exhibitors should ensure that the attire of al staff they deploy at their booth (whether the exhibitor’s direct employees or their contractors) be considered appropriate in a professional environment. Attire of an overly revealing or suggestive nature is not permitted. Examples of such attire may include but are not restricted to:

Tops displaying excessive cleavage;

Tank tops, halter tops, camisole tops or tube tops;

Miniskirts or minidresses;

Shorts;

Lycra (or other Second-Skin) bodysuits;

Objectionable or offensive costumes.

These guidelines are applicable to all booth staff, regardless of gender, and will be strictly enforced. We reserve the right to request that individual booth staff change their attire or leave the premises immediately if we feel their appearance might be offensive to other exhibitors or attendees.

讓我想起 2009 年 Yahoo! 辦的 Taiwan Open Hack Day：「Yahoo Sorry About Lap Dancers at Hack Day in Taiwan–So What's the Excuse for Last Year's Go-Go Girls?」。

用 Intel 網卡上的 Flow Director 過濾封包

在「Traffic filtration using NIC capabilities on wire speed (10GE, 14Mpps)」這邊看到的技巧。

作者建議另外安裝 driver，因為 Linux kernel 內的 driver 功能有限：「Intel Ethernet Drivers and Utilities」。

重點在 ethtool 這個工具，可以看到條件設定：

ethtool --help:
        ethtool -N|-U|--config-nfc|--config-ntuple DEVNAME    Configure Rx network flow classification options or rules
        rx-flow-hash tcp4|udp4|ah4|esp4|sctp4|tcp6|udp6|ah6|esp6|sctp6 m|v|t|s|d|f|n|r... |
        flow-type ether|ip4|tcp4|udp4|sctp4|ah4|esp4
            [ src %x:%x:%x:%x:%x:%x [m %x:%x:%x:%x:%x:%x] ]
            [ dst %x:%x:%x:%x:%x:%x [m %x:%x:%x:%x:%x:%x] ]
            [ proto %d [m %x] ]
            [ src-ip %d.%d.%d.%d [m %d.%d.%d.%d] ]
            [ dst-ip %d.%d.%d.%d [m %d.%d.%d.%d] ]
            [ tos %d [m %x] ]
            [ l4proto %d [m %x] ]
            [ src-port %d [m %x] ]
            [ dst-port %d [m %x] ]
            [ spi %d [m %x] ]
            [ vlan-etype %x [m %x] ]
            [ vlan %x [m %x] ]
            [ user-def %x [m %x] ]
            [ action %d ]
            [ loc %d]] |
        delete %d

看起來 stateless 的過濾可以在上面做...

Treasure Data 用 AWS 的方法

在 Zite 上看到「Treasure Data and AWS - Developers.io 2015」這篇，可以看看 Treasure Data 遇到的問題以及他們的解法。

這種文章除了看「怎麼做」以外，如果有提到「不怎麼做」也很值得看，也就是解釋避開了哪些東西。

像是他們拿 PostgreSQL 放 metadata 這件事情就很奇怪：

而他們解釋 Amazon S3 的 LIST 的品質有問題：

另外也說明了因為 GiST 的需求，所以不使用 MySQL，而且這也自動說明了 Amazon DynamoDB 不符合需求：

另外也遇到與 Netflix 同樣的問題，寫進去後因為 S3 的 Eventually Consistent 性質，不保證馬上讀的到：

如果沒有用到 GiST，用 DynamoDB 放 metadata 好像可以解決問題...

2014 年 Turing Award 得主：Michael Stonebraker

今年的 Turing Award 頒給了在資料庫領域上有重要貢獻的 Michael Stonebraker：

For fundamental contributions to the concepts and practices underlying modern database systems.

ACM 的頁面上列了不少成就，比較熟的是 PostgreSQL，他是 PostgreSQL 發展重要的關鍵人物：(出自維基百科「PostgreSQL」條目)

PostgreSQL evolved from the Ingres project at the University of California, Berkeley. In 1982 the leader of the Ingres team, Michael Stonebraker, left Berkeley to make a proprietary version of Ingres. He returned to Berkeley in 1985 and started a post-Ingres project to address the problems with contemporary database systems that had become increasingly clear during the early 1980s. The new project, POSTGRES, aimed to add the fewest features needed to completely support types. These features included the ability to define types and to fully describe relationships – something used widely before but maintained entirely by the user.