510fe1353d
live_migration_progress_timeout aims to timeout a live-migration well before the live_migration_completion_timeout limit, by looking for when it appears that no progress has been made copying the memory between the hosts. However, it turns out there are several problems with the way we monitor progress. In production, and stress testing, having live_migration_progress_timeout > 0 has caused random timeout failures for live-migrations that take longer than live_migration_progress_timeout One problem is that block_migrations appear to show no progress, as it seems we only look for progress in copying memory. Also the way we query QEMU via libvirt breaks when there are multiple iterations of memory copying. We need to revisit this bug and either fix the progress mechanism or remove the all the code that checks for the progress (including the automatic trigger for post-copy). But in the mean time, lets default to having no timeout, and warn users that have overridden this configuration by deprecating the live_migration_progress_timeout configuration option. For users concerned about live-migration timeout errors, I have cleaned up the configuration option descriptions, so they have a better chance of stopping the live-migration timeout errors they may come across. Related-Bug: #1644248 Change-Id: I1a1143ddf8da5fb9706cf53dbfd6cbe84e606ae1
17 lines
794 B
YAML
17 lines
794 B
YAML
---
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issues:
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The live-migration progress timeout controlled by the configuration option
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``[libvirt]/live_migration_progress_timeout`` has been discovered to
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frequently cause live-migrations to fail with a progress timeout error,
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even though the live-migration is still making good progress.
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To minimize problems caused by these checks we have changed the default
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to 0, which means do not trigger a timeout.
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To modify when a live-migration will fail with a timeout error, please now
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look at ``[libvirt]/live_migration_completion_timeout`` and
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``[libvirt]/live_migration_downtime``.
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deprecations:
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``[libvirt]/live_migration_progress_timeout`` has been deprecated as this
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feature has been found not to work. See bug 1644248 for more details.
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