Very low ARC Hit Ratio

[djdwosk97]

ARC is mostly going to do useful stuff on moderately-to-insanely busy systems. It is less beneficial elsewhere, and is not that beneficial in cases where there's a lot of totally random access to the pool.

I'm more concerned with the low arc being a symptom of another problem.

 

[jgreco]

And what problem would that be....?

 

[djdwosk97]

And what problem would that be....?

I have no idea, but since my ARC went down when I added more RAM (and upgraded the cpu/board) I just assumed there was something (bad) going on that was stopping something from working at 100%.

 

[jgreco]

Wait and see over time. ARC really is a long term cache, rather than a short term cache of the sort we normally think of with the word cache. Given sufficient room, the ARC (and L2ARC) will tend to cache everything that is of interest, but rapid activity on a small ARC makes it hard to figure out what is of value.