Vmm /
Optimize

11:53 < mlarkin> so jrmu the first thing I would do is crank host HZ to 1000 
                 or 2000
11:53 < jrmu> I'll take your word for it then
11:53 < mlarkin> that will make an immediate improvement
11:53 < mlarkin> leave the guests at 100
11:53 < jrmu> ok so I'd do that with the BIOS settings right?
11:53 < mlarkin> no
11:53 < mlarkin> param.h
11:54 < mlarkin> rebuild host kernel
11:54 < mlarkin> sorry param.c
11:54 < mlarkin> try 1000
11:54 < mlarkin> that usually always works
11:54 < mlarkin> my success rate with 2000 is more hit/miss
11:55 < mlarkin> and whatever you do, dont come to tech@/misc@ and complain 
                 that HZ=1000 is breaking things.
11:55 < mlarkin> this is just "hallway conversation"
11:55 < brynet> I think Misha had a page for tuning things, talk with him. 
                Also would recommend checkout out Dave Voutila's vmm_clock 
                and virtio_vmmci drivers.
11:55 < jrmu> :) ok thank you
11:56 < brynet> https://github.com/voutilad
11:56 < mlarkin> HZ=1000 allows for more efficient servicing of guest clock 
                 interrupts
11:56 < mlarkin> if 1000 works for a while with "lots" of vms, try 2000
11:56 < brynet> (If you're planning on Linux VMs, that is.)
11:57 < mlarkin> brynet: HZ=1000 helps with any guests
11:57 < brynet> right, meant dv@'s drivers. :)
11:57 < mlarkin> anything > 100
11:57 < mlarkin> ah
11:57 < mlarkin> yes
11:58 < mlarkin> cheloha@ is working on a better clock subsystem that will 
                 fix a lot of this but it is a ways away still. to give you 
                 an idea how hard that is, he has been continuously working 
                 on it since 2019
11:58 < mlarkin> for now, cranking HZ is the only solution we have
11:58 < jrmu> thanks, that is interesting, I'll research into it more later
11:58 < jrmu> I'll put this in my notes