jboner

Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD

myano

Merging A Forked Gist Into Your Gist

Let's say you have a gist (public or private) and someone forks it and makes changes to it. Awesome! However, now you want to merge in their changes to your gist. Unfortunately, it doesn't seem GitHub supports this via their website at the moment, however, you can still merge the gists with 'git' on the command line.

1. You want to clone your gist. You can locate the link for this under "Clone this gist"

    ➜  ~/dev » git clone https://gist.github.com/5315168.git
    Cloning into '5315168'...
   

remote: Counting objects: 6, done.

jahe

// Enable component-scanning and auto-configuration with @SpringBootApplication Annotation
// It combines @Configuration + @ComponentScan + @EnableAutoConfiguration
@SpringBootApplication
public class FooApplication {
  public static void main(String[] args) {
    // Bootstrap the application
    SpringApplication.run(FooApplication.class, args);
  }
}

0xjac

The repository for the assignment is public and Github does not allow the creation of private forks for public repositories.

The correct way of creating a private frok by duplicating the repo is documented here.

For this assignment the commands are:

1. Create a bare clone of the repository. (This is temporary and will be removed so just do it wherever.)

git clone --bare [email protected]:usi-systems/easytrace.git

hackjutsu

git branch --set-upstream-to <remote-branch>
# example
git branch --set-upstream-to origin feature-branch

# show up which remote branch a local branch is tracking
git branch -vv

sets the default remote branch for the current local branch.

jahe

/*
JPA (Java Persistence API)

Transaction Management with an Entity-Mananger:
---
entityManager.getTransaction().begin();
entityManager.persist(<some-entity>);
entityManager.getTransaction().commit();
entityManager.clear();

connor11528