vmm: migration: streamline and cleanup memory_copy_iterations() #72
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Users with Nix and a shell with direnv integration will be able to automatically enter the Nix development shell. Forgot to add this in [0]. [0] cyberus-technology#73 On-behalf-of: SAP philipp.schuster@sap.com Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
This is the first commit in a series of improvements `memory_copy_iterations()` and `struct MigrationState`. I verified everything in dozens of test runs with excessive logging together with three colleagues (StefanK, PascalS, SebastianE). The series is a pre-requisite for live migration statistics reporting. Previously, the initial transmission was done in a dedicated step and `memory_copy_iterations()` took only care of the delta transmission. This makes aggregating metrics unnecessarily difficult. Therefore, everything is now handled gracefully by `memory_copy_iterations()` in one single place. Further, this consolidation perfectly makes sense as all memory transmission is now streamlined in one function. I had to adapt the iteration counter: Iteration 0 : initial transmission Iteration 1..n: delta transmission ^ done inside the function Iteration n : final transmission ^ done outside the function On-behalf-of: SAP philipp.schuster@sap.com Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
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amphi
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I just have one nit, feel free to ignore it.
This improves the code quality of `struct MigrationState` and memory_copy_iterations(). This significantly improves maintainability of the code. Further, I've added the ability for expected downtime calculation and dirty page calculation. The new names are much more descriptive. I also removed properties that didn't make sense. These changes have undergone intense manual testing where many colleagues attended (PascalS, StefanK, SebastianE). There is currently no easy way to check that things really work as a reviewer. PS: The old struct comes from an external contributor [0]. [0] cloud-hypervisor#7033 On-behalf-of: SAP philipp.schuster@sap.com Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
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This is a cleanup and also a prerequisite for #43 (migration statistics). It ensures maintainability of the code and also adds a (very basic) dirty rate calculation.
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