MB to MiB

I did not study computer science, so correct me if I'm wrong. But I think you are calculating mebibyte (MiB) not megabyte (MB). Megabyte would be:
... round($valueInByte / 1000 / 1000, 2).'MB ...
Or is there some specific standard you follow? According to https://en.wikipedia.org/wiki/Binary_prefix both calculations (yours and mine) are correct in a way but I find yours to be not completely clear.

src/Composer/Console/Application.php

@@ -262,7 +262,7 @@ class Application extends BaseApplication
             }
 
             if (isset($startTime)) {
-                $io->writeError('<info>Memory usage: '.round(memory_get_usage() / 1024 / 1024, 2).'MB (peak: '.round(memory_get_peak_usage() / 1024 / 1024, 2).'MB), time: '.round(microtime(true) - $startTime, 2).'s');
+                $io->writeError('<info>Memory usage: '.round(memory_get_usage() / 1024 / 1024, 2).'MiB (peak: '.round(memory_get_peak_usage() / 1024 / 1024, 2).'MiB), time: '.round(microtime(true) - $startTime, 2).'s');
             }
 
             restore_error_handler();