Re: [PATCH 00/21] qemu: Refactor domstats code to avoid error reporting

On Mon, Feb 24, 2025 at 09:33:51 +0000, Daniel P. Berrangé wrote: > On Thu, Feb 20, 2025 at 10:01:13AM +0100, Peter Krempa wrote: > > The workers of qemuDomainGetStats should not report errors if they can't > > fetch data; but rather omit the entries. Refactor the code to > > de-incentivize error reporting. > > Why shouldn't they report errors ? > > Can you give an example of a problem seen with error reporting ? Silently The API itself allows querying multiple VMs for stats. Now if fetching just one of the stats fields fails you'll get an error instead of returning stats for everything else. > dropping data has the problem that its hard for people to realize that > anything has gone wrong, and in some cases dropped data will be not > distinguishable from unimplemented data. The API explicitly documents this behaviour and was intended from the beginning: