How about ephemeral storage with the ssd?





发件人：Sang Tran Quoc <SangTQ8@fpt.com>
发送日期：2024-01-24 11:06:28
收件人：Karl Kloppenborg <kkloppenborg@resetdata.com.au>,"smooney@redhat.com" <smooney@redhat.com>,"openstack-discuss@lists.openstack.org" <openstack-discuss@lists.openstack.org>
抄送人：Cuong Truong Tran Quoc <CuongTTQ@fpt.com>
主题：RE: Mapping local SSD to virtual machine persistently

Hi @smooney@redhat.com , and @Karl Kloppenborg

 

Thanks for your helps. I also have questions regarding to your suggestion as below:

@smooney@redhat.com Did you mention about cinder-volume with LVM driver? I tested it before, but the performance does not meet the requirement cause of the transportation of data via iSCSI protocol and it hard to compare with direct attach via libvirt. Your second idea are using flavor with ephemeral disk, right?  

@Karl Kloppenborg Your workaround suggestion looks good to me; I will search around for the accurate RabbitMQ event as you mentioned.

 

Best Regards

Sang.

 

From: Karl Kloppenborg <kkloppenborg@resetdata.com.au>
Sent: Wednesday, January 24, 2024 6:45 AM
To: smooney@redhat.com; Sang Tran Quoc <SangTQ8@fpt.com>; openstack-discuss@lists.openstack.org
Subject: Re: Mapping local SSD to virtual machine persistently

 

Hey guys,

 

One suggestion which might help you as a work around:

 

Libvirt regenerates the xml’s based on nova receiving events via the RabbitMQ event bus.

One option (which will require a bit of programming on your part) is to listen to the events that might impact the libvirt generation and execute the commands on your behalf.

This would necessitate knowing/storing that VM->Device mapping somewhere, i.e a database.

 

Thanks,
Karl.

 

From: smooney@redhat.com <smooney@redhat.com>
Date: Tuesday, 23 January 2024 at 10:04 pm
To: Sang Tran Quoc <SangTQ8@fpt.com>, openstack-discuss@lists.openstack.org <openstack-discuss@lists.openstack.org>
Subject: Re: Mapping local SSD to virtual machine persistently

On Tue, 2024-01-23 at 10:30 +0000, Sang Tran Quoc wrote:
>
> Hello community,
>
> I've got a question related to the raw device mapping to the OpenStack virtual machine. The situation is I have
> several SSDs along with my compute node and I would like to attach these SSDs to my virtual machine for enhancing the
> disk performance. My current solution is using command "virsh attach-disk <dom> <host-device> <guest-device>" but it
> not persistently and need to manual re-attach after hard-rebooting which lead to re-generate the xml vm structure.
> So, I wonder if there is an official solution for my problems. Thank you and welcome for every help in our community.

This is currenly not supported in openstack.

we have discussed adding local storage functionality to nova in the past but its non triavial since we woudl need
a new rest api to allow attaching/detaching them and schduelr intengration.

unfortuntly that means that today you cannot achive your goal. if you need to attach addtional storage dynamically your
only option is cinder volumes. you can provide addtional storage in the flavor but only statical
>
> Best regards,
> Sang Tran