Well, I enable THP indeed, there is no effect in my VM. The only huge improvement that I really saw went when enable cache=writeback. No KVM is goin' high!
2016-07-15 11:48 GMT-03:00 Alexandre DERUMIER <[email protected]>: > >>What is big memory in this context? how many GB? > > default page are 4k , THP are 2MB. > > If you need to access 2MB memory, with 4K pages, you need to do 512calls. > with THP only 1 call. > > That's why it's faster. > > The more memory the vm need to address , the more benefit you'll have. > You can enable it by default if you want. > > The only problem with THP, is that some workload are not happy with it, > because THP need to defragment pages sometime. > > > They are also a new option in proxmox , since last month : static > hugepages. > > you can add: > > hugepages : 2|1024 > > to force 2mb hugepage or 1GB hugepages for this specific vm. > > (Note that in this case, the memory is reserved. So, no fragmentation can > occur, but KSM is not working with this memory area) > > > ----- Mail original ----- > De: "Gilberto Nunes" <[email protected]> > À: "proxmoxve" <[email protected]> > Envoyé: Vendredi 15 Juillet 2016 14:27:37 > Objet: Re: [PVE-User] THP > > Hi > > I think Alexandre means big huge page memory... Some databases, like SQL > and Oracle, when have big tables, views, whatever, tend to use big page > memory in the file system. > > > > 2016-07-15 9:22 GMT-03:00 Lindsay Mathieson <[email protected]>: > > > On 15/07/2016 9:48 PM, Alexandre DERUMIER wrote: > > > >> It should improve performance for vms with big memory (like database for > >> example) > >> > > > > > > > > What is big memory in this context? how many GB? > > > > -- > > Lindsay Mathieson > > > > > > _______________________________________________ > > pve-user mailing list > > [email protected] > > http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-user > > > > > > -- > > Gilberto Ferreira > +55 (47) 9676-7530 > Skype: gilberto.nunes36 > _______________________________________________ > pve-user mailing list > [email protected] > http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-user > > _______________________________________________ > pve-user mailing list > [email protected] > http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-user > -- Gilberto Ferreira +55 (47) 9676-7530 Skype: gilberto.nunes36 _______________________________________________ pve-user mailing list [email protected] http://pve.proxmox.com/cgi-bin/mailman/listinfo/pve-user
