[pve-devel] less cores more iops / speed

[Alexandre DERUMIER]

Ok, I hope Intank will look at librbd and find the bottleneck !



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

De: "Stefan Priebe" <s.priebe at profihost.ag> 
À: "Alexandre DERUMIER" <aderumier at odiso.com> 
Cc: pve-devel at pve.proxmox.com, "Dietmar Maurer" <dietmar at proxmox.com> 
Envoyé: Mardi 13 Novembre 2012 08:59:41 
Objet: Re: [pve-devel] less cores more iops / speed 

Not sure which component limits the speed. There's no measurable 
component running at 100% CPU load. Or 100% network load... 

Stefan 

Am 13.11.2012 08:46, schrieb Alexandre DERUMIER: 
>> so around 3000 iops by node, I hope It'll improve in time. 
>>> Yes at least it scales. Sadly only 3000 iops... but each node has a 
> 
>>> capacity of 360.000 iops... perhaps a bit overkill... but SSDs are near 
>>> cheap as SAS drives... 
> 
> So, If you launch fio from differents kvm guest on differents kvm host, you are limited by the ceph cluster speed ? 
> 
> 
> ----- Mail original ----- 
> 
> De: "Stefan Priebe" <s.priebe at profihost.ag> 
> À: "Alexandre DERUMIER" <aderumier at odiso.com> 
> Cc: pve-devel at pve.proxmox.com, "Dietmar Maurer" <dietmar at proxmox.com> 
> Envoyé: Lundi 12 Novembre 2012 23:37:14 
> Objet: Re: [pve-devel] less cores more iops / speed 
> 
> Am 09.11.2012 15:43, schrieb Alexandre DERUMIER: 
>>>> To me yes. With 3 Nodes i had a max of 10.000 iops. 
>> 
>> Ah, great to known ! 
>> 
>> so around 3000 iops by node, I hope It'll improve in time. 
> Yes at least it scales. Sadly only 3000 iops... but each node has a 
> capacity of 360.000 iops... perhaps a bit overkill... but SSDs are near 
> cheap as SAS drives... 
> 
>> Did you have tested with gigabit link with bigger latencies ? 
> No. But i hope i can compare Arista 10G against HP 10G soon. 
> 
> Stefan 
> 
> 
>> ----- Mail original ----- 
>> 
>> De: "Stefan Priebe - Profihost AG" <s.priebe at profihost.ag> 
>> À: "Alexandre DERUMIER" <aderumier at odiso.com> 
>> Cc: pve-devel at pve.proxmox.com, "Dietmar Maurer" <dietmar at proxmox.com> 
>> Envoyé: Vendredi 9 Novembre 2012 15:28:12 
>> Objet: Re: [pve-devel] less cores more iops / speed 
>> 
>> Am 09.11.2012 11:31, schrieb Alexandre DERUMIER: 
>>>>> Yes. CPU Load in Ceph for rand. 4k writes can be dropped by 50% when 
>>>>> disabling all debug setting (see my last post on ceph mailinglist). 
>>> 
>>> I just see it, great,I'll test it on my side :) 
>>> 
>>> (how many ssds - nodes ?) I hope that Intank is working on random io performance. 
>> I have 5 nodes with 4 SSDs each. 
>> 
>>> I don't understand why we can't get more iops, if they are no cpu or disks bottleneck... (or they are locks somewhere ....) 
>>> 
>>> I really would like to known if iops scale with the number of nodes... 
>> 
>> To me yes. With 3 Nodes i had a max of 10.000 iops. 
>> 
>> Stefan 
>>