Солярис объемы ZFS: рабочая нагрузка, не поражающая L2ARC

У вас должно быть больше оперативной памяти в системе. Указатели на L2ARC должны храниться в ОЗУ (ARC), поэтому я думаю, что вам потребуется около 4 или 6 ГБ ОЗУ, чтобы лучше использовать ~ 60 ГБ L2ARC, которые у вас есть.

Это из недавнего треда по ZFS. список:

http://opensolaris.org/jive/thread.jspa?threadID=131296

L2ARC is "secondary" ARC. ZFS attempts to cache all reads in the ARC 
(Adaptive Read Cache) - should it find that it doesn't have enough space 
in the ARC (which is RAM-resident), it will evict some data over to the 
L2ARC (which in turn will simply dump the least-recently-used data when 
it runs out of space). Remember, however, every time something gets 
written to the L2ARC, a little bit of space is taken up in the ARC 
itself (a pointer to the L2ARC entry needs to be kept in ARC). So, it's 
not possible to have a giant L2ARC and tiny ARC. As a rule of thumb, I 
try not to have my L2ARC exceed my main RAM by more than 10-15x (with 
really bigMem machines, I'm a bit looser and allow 20-25x or so, but 
still...). So, if you are thinking of getting a 160GB SSD, it would be 
wise to go for at minimum 8GB of RAM. Once again, the amount of ARC 
space reserved for a L2ARC entry is fixed, and independent of the actual 
block size stored in L2ARC. The jist of this is that tiny files eat up 
a disproportionate amount of systems resources for their size (smaller 
size = larger % overhead vis-a-vis large files).