- Joined
- Dec 8, 2017
- Messages
- 442
I'm trying to understand how ARC hit ratio is calculated, and not getting very far googling. My hit ratio seems to sit at well over 90% most of the time. I just did a 3TB transfer of data from one pool to another, and noticed that during that period of time it went down to about 80%. I've got 192GB of RAM, and this data is never accessed, so there's no way that 80% of it was coming from the cache. If it was, I'd assume that it would be from the MRU cache, which according to arc_summary.py is 30GB.
What does the ARC hit ratio actually mean? How could it remain so high while doing a file transfer where almost none of the data should be in ARC?
Graph during file transfer:
What does the ARC hit ratio actually mean? How could it remain so high while doing a file transfer where almost none of the data should be in ARC?
Graph during file transfer: