|
|
@@ -1644,3 +1644,26 @@ Security is a broad topic. Unless you have considerable experience, a security
|
|
|
|
|
|
* [Security guide for developers](https://github.com/FallibleInc/security-guide-for-developers)
|
|
|
* [OWASP top ten](https://www.owasp.org/index.php/OWASP_Top_Ten_Cheat_Sheet)
|
|
|
+
|
|
|
+## Appendix
|
|
|
+
|
|
|
+You'll sometimes be asked to do 'back-of-the-envelope' estimates. For example, you might need to determine how long it will take to generate 100 image thumbnails from disk or how much memory a data structure will take. The **Powers of two table** and **Latency numbers every programmer should know** are handy references.
|
|
|
+
|
|
|
+### Powers of two table
|
|
|
+
|
|
|
+```
|
|
|
+Power Exact Value Approx Value Bytes
|
|
|
+---------------------------------------------------------------
|
|
|
+7 128
|
|
|
+8 256
|
|
|
+10 1024 1 thousand 1 KB
|
|
|
+16 65,536 64 KB
|
|
|
+20 1,048,576 1 million 1 MB
|
|
|
+30 1,073,741,824 1 billion 1 GB
|
|
|
+32 4,294,967,296 4 GB
|
|
|
+40 1,099,511,627,776 1 trillion 1 TB
|
|
|
+```
|
|
|
+
|
|
|
+#### Source(s) and further reading
|
|
|
+
|
|
|
+* [Powers of two](https://en.wikipedia.org/wiki/Power_of_two)
|
Donne Martin