This is a naive comparison between Akka actor and Java thread, as far as the performance is concerned. ‘Naive’ means there’s no complex logic or algorithm, but just a simple ping-pong program where two entities send messages to each other, in turns.

Although the performance tests are not thorough, nor they are real scenario, the comparison still gives a rough idea of Akka actor’s performance.

原文：Java Garbage Collection Distilled{:target=”_blank”}

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Recently, I am looking for the techniques for the company’s future
PAAS platform, I’ve been focused on WS2, but also browsed some other
products.

Here’s some of my thoughts of IAAS, PAAS and WSO2.

Points to Keep in Mind

1. API Management
2. Strip off unnecessary components (for lightweight)
3. Develop Stratos components
4. Cloudify (configuration, communication, load balancing)
5. Security - WS Security, REST Security
6. Performance - Latency, Throughput, Downtime
7. Monitoring
8. Database - MongoDB?
9. Bloat about XML configuration
10. Identity Management
11. Upgrading
12. Backward compatible
13. Migration script

After reading the “Tracing an SSH Request” part of GitHub’s “How We
Made GitHub Fast” blog, I was wondering how this is done through ssh
(at least in an operational level).

So I tried it out on my computer, read the ssh man page, and discover
some interesting use of ssh.

GitHub’s blog article:
How We Made GitHub Fast

Overview

Reading GitHub’s blog article “How We made GitHub Fast”,
unfortunately, the article does not provide any graph. So I draw
something on paper (ugly though), to illustrate GitHub’s architecture.

一、什么是Monad

Haskell的函数是纯函数(pure function)，无法进行很多需要副作用(side-effect)的操作，如 IO，Logging等。因此引入了Monad的概念。IO等有副作用的操作都放入Monad中。想用Haskell写出有用的程序，必须理解Monad。