On Mon, Oct 10, 2011 at 08:00:07PM +0100, Steven Whitehouse wrote: > > The fact remains that caching "as much as possible" tends to be harmful, > > and some careful limiting would be a good investment. > > > There is a limit. The point is that the limit is dynamic and depends on > memory pressure.
the "as possible" part of "as much as possible". > The VM requests a reduction in the number of cached > objects when it wants to reduce the size of what we have cached. So the > larger the amount of RAM, the more inodes may be potentially cached. > > I don't agree that caching as much as possible (given the constraints > just mentioned) is bad. the "tends to" part meant that it can be good or bad, depending. > The more we cache, the more disk I/O is avoided so the better the > performance will be. You don't need to argue that more caching can be good. My point is it's not universally true in practice, as Bob's tests show.
