PostgreSQL performance on FreeBSD

[Alan Somers]

On Fri, Jun 3, 2016 at 11:26 AM, Konstantin Belousov
<kostikbel at gmail.com> wrote:
> On Fri, Jun 03, 2016 at 09:29:16AM -0600, Alan Somers wrote:
>> I notice that, with the exception of the VM_PHYSSEG_MAX change, these
>> patches never made it into head or ports.  Are they unsuitable for low
>> core-count machines, or is there some other reason not to commit them?
>>  If not, what would it take to get these into 11.0 or 11.1 ?
>
> The fast page fault handler was redesigned and committed in r269728
> and r270011 (with several follow-ups).
> Instead of lock-less buffer queues iterators, Jeff changed buffer allocator
> to use uma, see r289279.  Other improvement to the buffer cache was
> committed as r267255.
>
> What was not committed is the aggressive pre-population of the phys objects
> mem queue, and a knob to further split NUMA domains into smaller domains.
> The later change is rotten.
>
> In fact, I think that with that load, what you would see right now on
> HEAD, is the contention on vm_page_queue_free_mtx.  There are plans to
> handle it.

Thanks for the update.  Is it still recommended to enable the
multithreaded pagedaemon?