The problems found in arla 0.28 is fixed in 0.29. The speed problem is probably related to the verbose logging.
don't use ARLA 0.28...
... if you still want to work with your machine. There is a
debugging message omitted once in a while at LOG_EMERG.
So it gets quite annoying over the time.
Apart from that, I found ARLA 0.28 rather slow compared to 0.27.
Consider this a hint, not a warning.
An open, cross-platform journaling program.
A scientific plotting package.