You set shared_buffers way below what is suggested in Greg Smith book (25% or more of RAM) .. what is the rationale behind that rule of thumb ? Other values are more or less what I set, though I could lower the effective_cache_size and vfs.zfs.arc_max and see how it goes.
I think those 25% rules were typically created when ram was no more than 4-8GB.
for our highly transactional workload, at least, too large of a shared_buffers seems to slow us down, perhaps due to higher overhead of managing that many 8k buffers. I've heard other read-mostly workloads, such as data warehousing, can take advantage of larger buffer counts.
-- john r pierce N 37, W 122 santa cruz ca mid-left coast
