| CAP - Consistency, Availability and Partition-Tolerant | |
| The CAP principle states that in distributed computing when it comes | |
| to consistency (C), availability (A) and partition (P) | |
| resilience/tolerance you can have only two of the three. | |
| I was recently introduced to this principle and find it rather | |
| insightful. Basically you can't have your cake and eat it too, | |
| otherwise (computing) life would be too easy. |
| 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 |
$ git checkout --orphan NEWBRANCH
$ git rm -rf .
--orphan creates a new branch, but it starts without any commit. After running the above command you are on a new branch "NEWBRANCH", and the first commit you create from this state will start a new history without any ancestry.
You can then start adding files and commit them and they will live in their own branch. If you take a look at the log, you will see that it is isolated from the original log.
This list is meant to be a both a quick guide and reference for further research into these topics. It's basically a summary of that comp sci course you never took or forgot about, so there's no way it can cover everything in depth. It also will be available as a gist on Github for everyone to edit and add to.
###Array ####Definition: