I got a 3 TB host (physical) with Oracle without Traditional Hugepages. The DB will work even without hugepages... but how much memory will be lost - that's another story.
Disable the transparent Huge Pages and check this documentation - should be valid for oVirt 4.3 and OLVM 4.3 as they share the same source: https://access.redhat.com/documentation/en-us/red_hat_virtualization/4.3/html/virtual_machine_management_guide/configuring_high_performance_virtual_machines_templates_and_pools#Configuring_Huge_Pages Best Regards, Strahil Nikolov В сряда, 29 септември 2021 г., 15:20:54 ч. Гринуич+3, Tommy Sway <sz_cui...@163.com> написа: I’am 4.3, but the memory of the VM and the SGA is large , 32GB, so the vm should set the traditional hugepage for the database SGA. I don't know how to set up a large page on a KVM host. Because if I make it a traditional big page, how big should I make it? Will non-VM SGA usage of many VMs be affected? After all, not all memory used by QEMU needs to be HugePage, and traditional large page memory needs to be used by specific code calls and is not transparent. These are all questions. From: users-boun...@ovirt.org <users-boun...@ovirt.org> On Behalf Of Strahil Nikolov via Users Sent: Wednesday, September 29, 2021 5:39 PM To: Tommy Sway <sz_cui...@163.com>; 'users' <users@ovirt.org> Subject: [ovirt-users]Re: 回复: Re: About the vm memory limit If you are on 4.3 -> disable transparent hugepages both Hypervisor and VM. If you are using 4.4 -> disable transparent hugepages and also cobfigure regular huge pages. Best Regards, Strahil Nikolov > On Wed, Sep 29, 2021 at 5:34, Tommy Sway > <sz_cui...@163.com> wrote: > From the Oracle OLVM support: > > Configuring the Hugepages for guest VMs should be suffice, however, it needs > the KVM hosts too configured with the Hugepages. > Since, if it not you may end with issues while staring the guest VMs. > > I really don't know what to do now. > > > > > > -----Original Message----- > From: users-boun...@ovirt.org <users-boun...@ovirt.org> On Behalf Of Strahil > Nikolov via Users > Sent: Tuesday, September 28, 2021 3:39 PM > To: 'users' <users@ovirt.org>; Tommy Sway <sz_cui...@163.com> > Subject: [ovirt-users]Re: 回复: Re: About the vm memory limit > > I think that if you run VMs with Databases, you must disable transparent huge > pages on Hypervisour level and on VM level. Yet, if you wish you can use > regular huge pages on VM level. > > Best Regards, > Strahil Nikolov > > > > > > > В вторник, 28 септември 2021 г., 09:21:09 ч. Гринуич+3, Tommy Sway > <sz_cui...@163.com> написа: > > > > > > > What problem will appear if I use the default transparent huge page enabled > mode for physical hosts, but configure traditional huge page memory on the > virtual machine for database SGA ? > Or is it better to disable transparent huge page on physical machines and > still use traditional huge page memory on virtual machines? > > Which one is prefer ? > > > From: users-boun...@ovirt.org <users-boun...@ovirt.org> On Behalf Of Strahil > Nikolov via Users > Sent: Tuesday, September 28, 2021 12:05 AM > To: tommy <sz_cui...@163.com>; 'users' <users@ovirt.org> > Subject: [ovirt-users]Re: 回复: Re: About the vm memory limit > > https://docs.oracle.com/en/database/oracle/oracle-database/19/ladbi/disabling-transparent-hugepages.html > > https://access.redhat.com/solutions/1320153 (requires RH dev subscription or > other type of subscription) -> In short add 'transparent_hugepage=never' to > the kernel params > > SLES11/12/15 -> > https://www.suse.com/c/sles-1112-os-tuning-optimisation-guide-part-1/ > > > Best Regards, > Strahil Nikolov > > > > > >> On Mon, Sep 27, 2021 at 16:33, tommy <sz_cui...@163.com> wrote: >> thank you! >> >> and how to get the config info of Transparent huge pages and how to >> disable it? >> >> >> >> >> >> 发自我的华为手机 >> >> >> -------- 原始邮件 -------- >> 发件人: Strahil Nikolov <hunter86...@yahoo.com> >> 日期: 2021年9月27日周一 21:13 >> 收件人: 'users' <users@ovirt.org>, Tommy Sway <sz_cui...@163.com> >> 主 题: Re: [ovirt-users] Re: About the vm memory limit>> Transparent huge >> pages are enabled by default, so you need to stop >> them.I would use huge >> pages on both host and VM, but theoretically it >> shouldn't be a problem >> running a VM with enabled HugePages without >> configuring on Host.Best >> Regards,Strahil NikolovВ събота, 25 >> септември 2021 г., 15:25:10 ч. >> Гринуич+3, Tommy Sway >> <sz_cui...@163.com> написа: transparent huge pages >> are not used on vm >> and physical host. But, can I enable hugepage memory >> on virtual >> machines but not on a physical machine?For database running >> on vm, >> and it needs to config hugepage. From: Strahil Nikolov >> >> <hunter86...@yahoo.com> Sent: Saturday, September 25, 2021 5:32 PMTo: >> >> Tommy Sway <sz_cui...@163.com>Subject: Re: [ovirt-users] About the vm >> >> memory limit It depends on the numa configuration of the host. If you >> >> have 256G per CPU, it's best to stay into that range. Also, consider >> >> disabling transparent huge pages on the host & VM. Since 4.4 Regular >> Huge >> Pages (do not confuse them with THP) can be used on the >> Hypervisors, >> while on 4.3 there were some issues but I can't provode >> any details. Best >> Regards,Strahil Nikolov> On Fri, Sep 24, 2021 at >> 6:40, Tommy Sway> >> <sz_cui...@163.com> wrote:> I would like to ask if >> there is any limit on >> the memory size of virtual machines, or >> performance curve or something >> like that?> As long as there is memory >> on the physical machine, the more >> virtual machines the better?> > In >> our usage scenario, there are many >> virtual machines with databases, >> and their memory varies greatly. > For >> some virtual machines, 4G >> memory is enough, while for some virtual >> machines, 64GB memory is >> needed.> > I want to know what is the best use >> of memory for a >> virtual machine, since the virtual machine is just a QEMU >> emulation >> process on a physical machine, and I worry that it is not using >> as >> much memory as a physical machine. Understand this so that we can >> >> develop guidelines for optimal memory usage scenarios for virtual >> >> machines.> > Thank you!> > > >> >> _______________________________________________Users mailing list -- >> >> users@ovirt.orgTo unsubscribe send an email to >> >> users-leave@ovirt.orgPrivacy Statement: >> >> https://www.ovirt.org/privacy-policy.htmloVirt Code of Conduct: >> >> https://www.ovirt.org/community/about/community-guidelines/List >> Archives: >> >> https://lists.ovirt.org/archives/list/users@ovirt.org/message/Y6XDOIM>> >> KCP4JEJF7M5DLJ33U2ENJKGAN/___________________________________________>> >> ____Users mailing list -- users@ovirt.orgTo unsubscribe send an email >> to >> users-leave@ovirt.orgPrivacy Statement: >> >> https://www.ovirt.org/privacy-policy.htmloVirt Code of Conduct: >> >> https://www.ovirt.org/community/about/community-guidelines/List >> Archives: >> >> https://lists.ovirt.org/archives/list/users@ovirt.org/message/3YHTUBA>> >> G42YRNEUCWG4DF5TEP2I22DMH/_______________________________________________Users >> mailing list -- users@ovirt.orgTo unsubscribe send an email to >> users-le...@ovirt.org Privacy Statement: >> https://www.ovirt.org/privacy-policy.htmloVirt Code of Conduct: >> https://www.ovirt.org/community/about/community-guidelines/List Archives: >> https://lists.ovirt.org/archives/list/users@ovirt.org/message/GRNMITHSDUEUB2JL2HM522ZGBTF4OPIC/ > _______________________________________________Users mailing list -- > users@ovirt.orgTo unsubscribe send an email to users-leave@ovirt.orgPrivacy > Statement: https://www.ovirt.org/privacy-policy.htmloVirt Code of Conduct: > https://www.ovirt.org/community/about/community-guidelines/List Archives: > https://lists.ovirt.org/archives/list/users@ovirt.org/message/QBQHER4G2VLM6IVZ45XUZNV6AUEE4AR5/ > _______________________________________________ Users mailing list -- users@ovirt.org To unsubscribe send an email to users-le...@ovirt.org Privacy Statement: https://www.ovirt.org/privacy-policy.html oVirt Code of Conduct: https://www.ovirt.org/community/about/community-guidelines/ List Archives: https://lists.ovirt.org/archives/list/users@ovirt.org/message/XZ7PQ6ZHZP5Q6V3PUCOFNYGKTUW4BW67/