Thank you for all the replies. This is one of the reasons why Cloudstack is successful. The people involved with it 😊 Thank you for being an amazing group.
The issue was fixed by matching the CS versions. After the update, I noticed a new error in the database. 2025-11-06 09:04:42,048 ERROR [o.a.c.f.m.MessageBusBase] (pool-170-thread-1:[]) (logid:) NO EVENT PUBLISH CAN BE WRAPPED WITHIN DB TRANSACTION! com.cloud.utils.exception.CloudRuntimeException: NO EVENT PUBLISH CAN BE WRAPPED WITHIN DB TRANSACTION! As for my snapshot issue, I did see I am using QCOW, and then only when performing with memory snapshots, did the pause happen.     Marty From: Nicolas Vazquez <[email protected]> Date: Thursday, November 6, 2025 at 6:45 AM To: [email protected] <[email protected]> Subject: Re: KVM, Snapshots, and QCOW2 WARNING: This email originated from outside of the organization. Do not click links or open attachments unless you recognize the sender and know the content is safe. Hi Marty and Joao, Just adding to the questions raised by Joao - Marty I could check on another thread email from you that you were using 4.20.1 for the management server and 4.21 on the KVM agents. Is it still the case for this issue? If that is the case, can you keep the same version for both packages and retry the operations? Regards, Nicolas Vazquez From: João Jandre Paraquetti <[email protected]> Date: Thursday, 6 November 2025 at 8:32 AM To: [email protected] <[email protected]> Subject: Re: KVM, Snapshots, and QCOW2 Hello, Marty The volume format is determined by the hypervisor + storage type used. Generally speaking, when working with KVM, file-based storages (like NFS, shared mount point and local storage) use QCOW2, and other storage types, such as RBD (Ceph,) use RAW. Could you share which storage type you are using for your primary storage? Furthermore, there are differences in implementation when using volume and instance snapshots, could you share which type of snapshots are you trying to take? I'm not familiar with snapshot creation when using RAW volumes, but when using QCOW2 and file-based storage, the VMs should not be paused during the whole process, at least in the latest versions. Best regards, João Jandre. On 11/5/25 18:41, Marty Godsey wrote: > Hello, > > On my KVM cluster, which is new and not in production yet since I am still > tuning, I noticed that snapshots were taking a long time to complete. And > when say a long time, I mean 45seconds to 1 min. The VM is, of course, > paused when this happens. As you can imagine, this is unusable. The > connection to the NFS storage is 100G and all NVME. While a snapshot is > running, I can see it hitting the storage really hard. I then looked at the > KVM process for that VM on the KVM server and it looks like it is using RAW > for the format. > > I created this VM by spinning up a new VM in CloudStack so I could make my > template. > > So I have a couple questions. How do I specify QCOW2 when making new volumes > or spinning up new VMs and I assume that snapshots should not take this long, > correct? > > Thank you for all your help. > > Nicolas Vazquez Lead Software Engineer s: +44 20 3603 0540 e: [email protected] | w: http://atpscan.global.hornetsecurity.com?d=NkXnHB5ZK4qBZPc-Edqj1zeEZ-MPTIXT1P0FsJatjJU&f=-7YejJ3wRYbNAtNEDVRTHAzJdqfd51MpeTKQDbeKgZVasqlxZK0Yh6ri9ohqMyLY&i=&k=QjyV&m=1BIQnTb9mH16296Bx0HouWJtM1v3L51kutfYTcMgvBm0G8i3J8V3SICPc-QaQZ_EHJ6NFhQZ9MC74PP6vNU4HBGq641QIi7esw-rgWHZuCdhzBZOKy_BD2F_uIy42HsX&n=kJOV8uYUcHUr-Z8LEmrZ2N81MDvsqGDCaiBlfrNBRJXrj6Jr0zMbTHZK3B8r3USo&r=R__vCVQ59JKeY3BsZ3SQTN2ZDUd533blNjEbukWNklv2joDW7kzrIF3pbnnkvOzM&s=f77cd1ef7242764b585981fb29323bc2494b8c82192c2d47a920949c16936fc7&u=www.shapeblue.com | t: @shapeblue a: 3 London Bridge Street, 3rd floor, News Building, London SE1 9SG UK Shape Blue Ltd is a company incorporated in England & Wales. ShapeBlue is a registered trademark. This email and any attachments to it may be confidential and are intended solely for the use of the individual to whom it is addressed. Any views or opinions expressed are solely those of the author and do not necessarily represent those of Shape Blue Ltd or related companies. If you are not the intended recipient of this email, you must neither take any action based upon its contents, nor copy or show it to anyone. Please contact the sender if you believe you have received this email in error. Find out more about ShapeBlue and our range of CloudStack related services: IaaS Cloud Design Build | CloudStack Consulting | CloudStack Software Engineering CloudStack Infrastructure Support | CloudStack Bootcamp Training Courses
