This page is to collect observations and experiments related to performance of minix.

====== Starting point ======

There are countless ways to talk about performance, so let's start with one simple case that is both relevant for our daily usage and displays terrible performance: gcc and clang on minix.

====== Basic Observations ======

  * Clang is significantly slower than gcc on minix, and it's supposed to be faster.
  * There is high idle time when gcc and clang are executing, suggesting high i/o wait time

====== Experiments ======

(Timing measurements to be done.)

  * Run with huge primary cache: no more idle time. clang is still significantly slower than gcc though, and gcc still isn't very fast.
  * Run with /usr/tmp, /tmp and /usr/src on ramdisks: almost no idle time any more.
  * Marking unreferenced blocks as clean if they're dirty: happens but doesn't help much in real time.
  * Defer evicting dirty blocks from the cache, prefering a clean block even if it's older in order to batch write operations: helps with reducing flushall() calls but not much in real time.