[pve-devel] [PATCH] qemuserver : iothrottle add support for throttling burst max

[Alexandre DERUMIER]

>>What do you mean by 'true'? That just a reasonable setting which works for many people?
 
I mean, you can have different storage which can do same bandwith but a lot less iops

ssd : 6000iops  bandwith : 400MB/S
sas 15k : 150iops bandwith : 400MB/S


doing same  io_ops = bwlimit/32k , don't make sense if you have ssd or sas15k


Myself,currently, I limit only bandwith for vms which are doing sequential workload (need lot of bandwith but small ios)

And I limit ios for random workload (need a lot of ios but not big bandwith)

And with new burst option, you really need to known what the application in the vm is doing, to allow not too less or not much burst.




I don't known if it's easy to find a common way to compute all this values.


Maybe adding a wizard in pve-manager with to generate predifined values/worload for newbie users ?

And keep an advanced gui to manually defined values for expert users.




----- Mail original ----- 

De: "Dietmar Maurer" <dietmar at proxmox.com> 
À: "Alexandre DERUMIER" <aderumier at odiso.com> 
Cc: pve-devel at pve.proxmox.com, "Stefan Priebe" <s.priebe at profihost.ag> 
Envoyé: Jeudi 5 Décembre 2013 10:32:18 
Objet: RE: [pve-devel] [PATCH] qemuserver : iothrottle add support for throttling burst max 

> >>I would simply like to have (additionally) some simpler setting witch 
> >>usually fits most user's needs, for example a simple bandwidth: 
> >> 
> >>bwlimit = 100MB/s 
> >> 
> >>form that you can compute IO_OPS/s (assuming an artificial block size of 32k): 
> >> 
> >>io_ops = bwlimit/32k 
> 
> Can't be true for all workload, if you are doing random io or sequential io. 

What do you mean by 'true'? That just a reasonable setting which works for many people? 

> (generally I limit the bandwith for sequential workload and iops for random 
> workload) 

You can still do that (I don't want to remove those options). I just think about an easier 
way to limit bandwidth for people with less technical background (honestly, I think 99,9% 
of people will not understand those settings).