Re: zfs pool behavior - is it ever freed?

[mlelstv%serpens.de@localhost (Michael van Elst)]

gdt%lexort.com@localhost (Greg Troxel) writes:

>  RAM and/or responds to pressure.  That's why we see almost no reports
>  of trouble expect for zfs.


There is almost no pressure on pools and several effects prevent
pressure from actually draining pool caches.

There is almost no pressure on vcache and the ZFS equivalents. Impact
by ZFS is much higher, because of the amount of memory locked up
this way. These data structures are significant as these actually
reference other data structures and buffers.

Swapping out userland pages is done much earlier, so with high ZFS
utilization you end with a system that has a huge part of real memory
allocated to the kernel. When you run out of swap (and processes
already get killed), then you see some effects on kernel data.