| 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 |
This is a collection of the things I believe about software development. I have worked for years building backend and data processing systems, so read the below within that context.
Agree? Disagree? Feel free to let me know at @JanStette.
Keep it simple, stupid. You ain't gonna need it.
FWIW: I (@rondy) am not the creator of the content shared here, which is an excerpt from Edmond Lau's book. I simply copied and pasted it from another location and saved it as a personal note, before it gained popularity on news.ycombinator.com. Unfortunately, I cannot recall the exact origin of the original source, nor was I able to find the author's name, so I am can't provide the appropriate credits.
Locate the section for your github remote in the .git/config file. It looks like this:
[remote "origin"]
fetch = +refs/heads/*:refs/remotes/origin/*
url = git@github.com:joyent/node.git
Now add the line fetch = +refs/pull/*/head:refs/remotes/origin/pr/* to this section. Obviously, change the github url to match your project's URL. It ends up looking like this:
| This playbook has been removed as it is now very outdated. |
We have absolutely no idea what we're doing in tech. Please explain the utmost basic things to us.
We only do web design. Our whole reason of being in tech is to make things pretty. Consider us the doilies of the industry.
We're not laughing about your joke, so we clearly need you explain it to us. In great detail.
We're only in tech to find a husband, boyfriend or generally to get laid.
| # You don't need Fog in Ruby or some other library to upload to S3 -- shell works perfectly fine | |
| # This is how I upload my new Sol Trader builds (http://soltrader.net) | |
| # Based on a modified script from here: http://tmont.com/blargh/2014/1/uploading-to-s3-in-bash | |
| S3KEY="my aws key" | |
| S3SECRET="my aws secret" # pass these in | |
| function putS3 | |
| { | |
| path=$1 |
Since many deployments may start out with 3 nodes and so little is known about how to grow a cluster from 3 memebrs to 5 members without losing the existing Quorum, here is an example of how this might be achieved.
In this example, all 5 nodes will be running on the same Vagrant host for the purpose of illustration, running on distinct configurations (ports and data directories) without the actual load of clients.
YMMV. Caveat usufructuarius.
I use PostgreSQL via the psql client. If you use a different client (eg. pgAdmin, etc.), I don't know how much will translate over.
One nice difference between psql and mysql (cli) is that if you press CTRL+C, it won't exit the client.
psql -U postgres