Bug 1789647
| Summary: | VDSM does not report 'memoryStats' and memUsage is 0 on RHEL8 HP guest (no balloon device) | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Virtualization Manager | Reporter: | Germano Veit Michel <gveitmic> |
| Component: | vdsm | Assignee: | Tomasz Barański <tbaransk> |
| Status: | CLOSED CANTFIX | QA Contact: | meital avital <mavital> |
| Severity: | medium | Docs Contact: | |
| Priority: | unspecified | ||
| Version: | 4.3.7 | CC: | jortialc, lsurette, rbarry, srevivo, ycui |
| Target Milestone: | ovirt-4.4.1 | ||
| Target Release: | --- | ||
| Hardware: | x86_64 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | If docs needed, set a value | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2020-02-03 16:31:53 UTC | Type: | Bug |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | Virt | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
At this moment balloon device driver is the only way to get memory information from libvirt. When it's disabled, there's no way to read it. The libvirt team is not particularly happy to duplicate the functionality. Closing per comment#2. Without support from the underlying tools, we cannot resolve this Ack, documented in https://access.redhat.com/solutions/4727081 |
Description of problem: If a RHEL8 (without ovirt-guest-agent) VM has the Memory Balloon device disabled (either manually or by the high performance profile: 1) In Admin Portal, Memory usage of Guest is always 0% as vdsm reports memUsage as 0. 2) memoryStats are missing for the Guest, all memory stats in the API are 0 too. See: # vdsm-client VM getStats vmID=e0bff6bc-0f64-4264-b036-bd122e4c5f38 | egrep 'memUsage|memoryStats' "memUsage": "0", It looks like VDSM first looks for Balloon stats, and then falls back to ovirt-guest-agent. But RHEL8 does not have oga. https://github.com/oVirt/vdsm/blob/ovirt-4.3/lib/vdsm/virt/vm.py#L1799 https://github.com/oVirt/vdsm/blob/ovirt-4.3/lib/vdsm/virt/vmstats.py#L450 So without a balloon device this is not going to work. Also found you tried to add this to qemu-ga in the past: https://bugzilla.redhat.com/show_bug.cgi?id=1101915 Version-Release number of selected component (if applicable): * vdsm-4.30.38-1.el7ev.x86_64 * RHEL8 * qemu-guest-agent-2.12.0-88.module+el8.1.0+5013+4f99814c.1.x86_64 * no ovirt-guest-agent How reproducible: Always Steps to Reproduce: 1. Install RHEL8 Guest 2. Disable balloon device (Edit -> Resource Allocation) Note: Or enabling High Performance 3. Start VM Actual results: Incorrect stats Expected results: Correct stats