linux

Silent data corruption Linux Kernel

Beware: Silent data corruption discovered in Linux kernels 4.10-4.17

While debugging an issue in a new StorPool deployment we re-discovered a kernel bug that exists in some of the latest Linux kernels and causes silent data corruption. The setup is a virtualized environment where the kernel containing the bug was running on the host. The guests were KVM virtual machines with io=threads (the default Beware: Silent data corruption discovered in Linux kernels 4.10-4.17

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The weird interactions of cgroups and linux page cache in hypervisor environments

The weird interactions of cgroups and linux page cache in hypervisor environments

Here’s one case we’ve spent some time debugging, related to StorPool, VMs, cgroups, OOM (out-of-memory) killer and caching. Some of it should be useful to a lot of sysadmins out there. The issue started with a customer complaining: > It’s happening again, on this hypervisor VMs are being killed > by the OOM killer. This The weird interactions of cgroups and linux page cache in hypervisor environments

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