| 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 |
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.
L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns
Compress 1K bytes with Zippy ............. 3,000 ns = 3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns = 20 µs
SSD random read ........................ 150,000 ns = 150 µs
Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs
The count of contributions (summary of Pull Requests, opened issues and commits) to public repos at GitHub.com from Wed, 21 Sep 2022 till Thu, 21 Sep 2023.
Only first 1000 GitHub users according to the count of followers are taken. This is because of limitations of GitHub search. Sorting algo in pseudocode:
githubUsers
.filter(user => user.followers > 1000)
| Mute these words in your settings here: https://twitter.com/settings/muted_keywords | |
| ActivityTweet | |
| generic_activity_highlights | |
| generic_activity_momentsbreaking | |
| RankedOrganicTweet | |
| suggest_activity | |
| suggest_activity_feed | |
| suggest_activity_highlights | |
| suggest_activity_tweet |
about:config settings to harden the Firefox browser. Privacy and performance enhancements.
To change these settings type 'about:config' in the url bar.
Then search the setting you would like to change and modify the value. Some settings may break certain websites from functioning and
rendering normally. Some settings may also make firefox unstable.
I am not liable for any damages/loss of data.
Not all these changes are necessary and will be dependent upon your usage and hardware. Do some research on settings if you don't understand what they do. These settings are best combined with your standard privacy extensions
(HTTPS Everywhere No longer required: Enable HTTPS-Only Mode, NoScript/Request Policy, uBlock origin, agent spoofing, Privacy Badger etc), and all plugins set to "Ask To Activate".
In August 2007 a hacker found a way to expose the PHP source code on facebook.com. He retrieved two files and then emailed them to me, and I wrote about the issue:
http://techcrunch.com/2007/08/11/facebook-source-code-leaked/
It became a big deal:
http://www.techmeme.com/070812/p1#a070812p1
The two files are index.php (the homepage) and search.php (the search page)
| package main | |
| import ( | |
| "context" | |
| "flag" | |
| "fmt" | |
| "log" | |
| "net/http" | |
| "os" | |
| "os/signal" |
| #include <time.h> // Robert Nystrom | |
| #include <stdio.h> // @munificentbob | |
| #include <stdlib.h> // for Ginny | |
| #define r return // 2008-2019 | |
| #define l(a, b, c, d) for (i y=a;y\ | |
| <b; y++) for (int x = c; x < d; x++) | |
| typedef int i;const i H=40;const i W | |
| =80;i m[40][80];i g(i x){r rand()%x; | |
| }void cave(i s){i w=g(10)+5;i h=g(6) | |
| +3;i t=g(W-w-2)+1;i u=g(H-h-2)+1;l(u |
