2:33 a.m.
----- Original Message -----
From: "Utkarsh Singh" <utkarshsins(a)gmail.com>
To: users(a)ovirt.org
Cc: fsimonce(a)redhat.com
Sent: Friday, March 7, 2014 6:16:46 PM
Subject: GSoC 14 Idea Discussion - virt-sparsify integration
Hello,
I am Utkarsh, a 4th year undergrad from IIT Delhi and a GSoC-14
aspirant. I have been lately involved in an ongoing project Baadal
Cloud Computing Platform in my institute, which has got me interested
in oVirt for a potential GSoC project.
I was going through the virt-sparsify integration project idea. I have
gone through the architecture documentation on the oVirt website. As
far as I understand, the virt-sparsify integration needs to be done on
the VDSM daemon, and it's control is either going to be completely
independent of ovirt-engine (for example running it once every 24
hours), or it's something that is centrally controlled by the
ovirt-engine through XML/RPC calls. The details are not specified in
the project ideas page. I would like to ask -
The request to sparsifying the image is controlled by ovirt-engine.
The user will pick one (or eventually more) disk(s) that are not in use
(vm down) and he'll request to sparsify it/them.
1. What would be the proposed ideal implementation? (Central-Control
or Independent-Control)
Central-Control
2. Is virt-sparsify usage going to be automated or
administrator-triggered, or a combination of both?
administrator-triggered
There are some aspects of the idea, which I would like to discuss
before I start working on a proposal.
It's not necessary that an automated usage of virt-sparsify is limited
to any simple idea. Architecture documentation states that
ovirt-engine has features like Monitoring that would allow
administrators (and possibly users) to be aware of vm-guest
performance as well as vm-host performance. I am not very sure about
how this data is collected, Is it done through MoM, or Is this
directly done by VDSM, or is someone else doing this (for hosts). It
would be great if someone can explain that to me. This information
about vm-guest usage and vm-host health can help in determining how
virt-sparsify is to be used.
The vm/hosts statistics are gathered and provided by VDSM.
Anyway I would leave this part out at the moment. The virt-sparsify
command is a long running task and in the current architecture it
can be only an SPM task.
There is some ongoing work to remove the pool and the SPM (making
virt-sparsify operable by any host) but I wouldn't block on that.
I am also not very clear about the Shared Storage component in the
architecture. Does oVirt make any assumptions about the Shared
Storage. For example, the performance difference between running
virt-sparsify on NFS as compared to running it (if possible) directly
on storage hardware. If the Storage solution is necessarily a NAS
instance, then virt-sparsify on NFS mount is the only option.
The storage connections are already managed by vdsm and the volume
chains are maintained transparently in /rhev/data-center/...
There are few differences between image files on NFS/Gluster and images
stored on LVs but with regard to how to reach them it is transparent
(similar path).
Right now, I am in the process of setting up oVirt on my system, and
getting more familiar with the architecture. Regarding my experience.
I am acquainted with both Java and Python. I have little experience
with JBoss, but I have worked on some other Web Application Servers
like web2py and Play Framework. My involvement in Baadal Platform has
got me acquainted with libvirt/QEMU, the details of which I have
mentioned below (if anyone is interested).
Depending on the amount of time that you can dedicate to this project
it seems that you could tackle both the vdsm and ovirt-engine parts.
--
Federico