Re: [pve-devel] [PATCH ha-manager 09/11] manager: use static resource scheduler when configured

[Thomas Lamprecht <t.lamprecht@proxmox.com>]

Am 11/11/2022 um 10:28 schrieb Fiona Ebner:
> Am 10.11.22 um 15:37 schrieb Fiona Ebner:
>> @@ -206,11 +207,30 @@ my $valid_service_states = {
>>  sub recompute_online_node_usage {
> So I was a bit worried that recompute_online_node_usage() would become
> too inefficient with the new add_service_usage_to_node() overhead from
> needing to read the guest configs. I now tested it with ~300 HA services
> (minimal containers) running on my virtual test cluster.
> 
> Timings with 'basic' mode were between 0.0004 - 0.001 seconds
> Timings with 'static' mode were between 0.007 - 0.012 seconds
> 
> While about a 10-fold increase, it's not too dramatic at least. I guess
> that's what the caching of cfs files is for :)
> 
> Still, the function is currently not only called in the main loop in
> manage(), but also in next_state_recovery() and change_service_state().
> 
> With, say, 400 HA services each on 5 nodes, if a node fails there's
> 400 calls from changing to freeze

huh, freeze should only happen on graceful shutdown of a node, not
if it fails?

> 400 calls from changing to recovery
> 400 calls in next_state_recovery
> 400 calls from changing to started
> If we take a generous estimate that each call takes 0.1 seconds (there's
> 2000 services in total), that's 40+80+40 seconds in 3 bursts during the
> fencing and recovery period.

doesn't that lead to overly long run windows between watchdog updates?

> 
> Is that acceptable? Should I try to optimize how often the function is
> called?
> 

hmm, a quick look wouldn't hurt, but not required for now IMO - if it can
interfere with watchdog updates I'd sneak in updating it once in between
though.


ps. maybe you can have some of that info/stats here in the commit message
of this patch.