= 2010-07-27 = * [感想] 作對的事,縱使一個人的力量經過五六年累積也是可以有大的影響!! * [[Image(wiki:jazz/10-07-27:10-07-27_NCHC_搜尋排行榜.PNG,width=800)]] == Cloud Computing == * [http://www.runpc.com.tw/index_cloud.aspx RUN!PC 的雲端運算智庫] - 把一些新聞根據 IaaS, PaaS, SaaS 分類,還不錯的想法!! * [benchmark] [http://wiki.github.com/brianfrankcooper/YCSB/ Yahoo! Cloud Serving Benchmark (YCSB)] - [http://research.yahoo.com/node/3202 論文: Benchmarking Cloud Serving Systems with YCSB] * Yahoo 寫的效能測試軟體,YCSB 1.2 版支援 HBase, Cassandra, MongoDB * 從[http://www.brianfrankcooper.net/pubs/ycsb-socc-talk.ppt 論文簡報投影片]得到的[http://www.brianfrankcooper.net/pubs/ycsb-v4.pdf 結論]注意到幾件事情: * 若資料庫特性是一半讀一半寫,MySQL 大約在 7500 operations/sec 時會到達效能極限。若資料庫特性是 95% 讀 5% 寫,就沒看到明顯效能極限。 * HBase 寫入飛快,但讀取會稍微慢一點,而且讀取的效率不太線性。(寫入記憶體所以超快,但成本也比較高,查詢時重建紀錄) 加機器時,不會有明顯的效能差異 (跟 HDFS 一樣,要跑 balancer 才會搬資料)。 - Low Update Latency, Higher Read Latency * Cassandra 寫入稍微慢一點,讀取則比 HBase 快,特別是資料庫特性是 95% 讀取時比 HBase 快。加機器的時候,會需要一段時間才能讓效能穩定下來(這部分我覺得是副本架構造成的)。 * [[Image(jazz/10-07-27:10-07-27_cassandra_hbase_update_heavy.png,width=800)]] * [[Image(jazz/10-07-27:10-07-27_cassandra_hbase_read_heavy.png,width=800)]] * [[Image(jazz/10-07-27:10-07-27_cassandra_hbase_short_scans.png,width=800)]] * [[Image(jazz/10-07-27:10-07-27_cassandra_hbase_scale_up.png,width=800)]] == Embedded : Security == * 圖片來源:[http://whitepapers.opensystemsmedia.com/u/pdfs/WhitePaper.mocana_attacktrends_wp_wireless.pdf Attacks on Mobile and Embedded Systems: Current Trends] by [http://www.mocana.com Mocana] * [[Image(jazz/10-07-27:10-07-27_Hacking_Timeline.jpg,width=800)]] * [[Image(jazz/10-07-27:10-07-27_The_Internet_of_Things.jpg,width=800)]] * [[Image(jazz/10-07-27:10-07-27_Mobile_Security.jpg,width=800)]] * 圖片來源:[http://whitepapers.opensystemsmedia.com/u/pdfs/WhitePaper.whitepapermocanadeviceintegrityrpt_final_springpcn_nanocryptonanosec.pdf U.S. Unprepared for Internet Device Flood: Unaddressed Security Problems & Talent Drought Threaten Long-Term Commercial, Government Interests] By: Kurt Stammberger, CISSP, Adrian Turner and Mat Small, Mocana With: Rich Nass, Sarah Friar, Goldman Sachs * [[Image(jazz/10-07-27:10-07-27_Number_of_Networked_Devices.jpg,width=800)]] * [[Image(jazz/10-07-27:10-07-27_Device_Marketing.jpg,width=800)]] * [[Image(jazz/10-07-27:10-07-27_Malware_Trend.jpg,width=800)]] * [[Image(jazz/10-07-27:10-07-27_Smart_Meter_Trend.jpg,width=800)]]