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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


(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.
minixperformance.txt · Last modified: 2014/11/11 14:52 (external edit)