Added readme section regarding minimizing output file sizes

README.md

@@ -145,6 +145,16 @@ option when embedding into a library project is `ZF_LOG_LIBRARY_PREFIX`. It
 could be used to decorate zf_log exported symbols to avoid linker conflicts
 (when that library project is used in other project that is also uses zf_log).
 
+#### Minimizing Output File Size
+
+As part of zf_log's main to be small, log strings below the current log level
+can be compiled out using optimization features in modern compilers. In
+```Debug``` builds, unused strings may not be compiled out and a ```Release```
+build may be necessary. Not all compilers will be capable of optimizing out
+unused parts of a program, but gcc provides this functionality using the
+```-fdata-sections``` and ```-ffunction-sections``` compile flags, the link flag
+```-Wl,--gc-sections```, and size optimization flag ```-Os```.
+
 ### Embedding with CMake
 
 Another options is avaibale for projects that are using CMake. Copy