- Removed a warning related to Linux user namespaces and kernel version. Previously, if the feature gate `UserNamespacesSupport` was enabled, the kubelet warned when detecting a Linux kernel version earlier than 6.3.0. While user namespace support generally requires kernel 6.3 or newer, it can also work on older kernels. ([#130243](https://github.com/kubernetes/kubernetes/pull/130243), [@rata](https://github.com/rata))

### Bug or Regression

- Removed a warning around Linux user namespaces and kernel version. If the feature gate `UserNamespacesSupport` was enabled, the kubelet previously warned when detecting a Linux kernel version earlier than 6.3.0. User namespace support on Linux typically does still need kernel 6.3 or newer, but it can work in older kernels too. ([#131784](https://github.com/kubernetes/kubernetes/pull/131784), [@rata](https://github.com/rata)) [SIG Node]...

# MinIO Server Limits Per Tenant

For optimal production setup MinIO recommends Linux kernel version 4.x and later.

## Erasure Code (Multiple Drives / Servers)

| Item                                                            | Specification |
|:----------------------------------------------------------------|:--------------|
| Maximum number of servers per cluster                           | no-limit      |

   *       then sequentially accessing it could result in other processes dying. This is solvable
   *       via madvise(2), but that obviously doesn't exist in java.
   *   <li>Ordinary copy. Kernel copies bytes into a kernel buffer, from a kernel buffer into a
   *       userspace buffer (byte[] or ByteBuffer), then copies them from that buffer into the
   *       destination channel.
   * </ol>
   *

      - name: Enable KVM group perms
        # https://github.blog/changelog/2023-02-23-hardware-accelerated-android-virtualization-on-actions-windows-and-linux-larger-hosted-runners/
        run: |
          echo 'KERNEL=="kvm", GROUP="kvm", MODE="0666", OPTIONS+="static_node=kvm"' | sudo tee /etc/udev/rules.d/99-kvm4all.rules
          sudo udevadm control --reload-rules
          sudo udevadm trigger --name-match=kvm

Each node is responsible of healing its local drives; Each drive will have multiple heal workers which is the quarter of the number of CPU cores of the node or the quarter of the configured nr_requests of the drive (https://www.kernel.org/doc/Documentation/block/queue-sysfs.txt). It is also possible to provide a custom number of workers by using this command: `mc admin config set alias/ heal drive_workers=100` .


```
~ mc admin config set alias/ heal

| `minio_system_process_syscall_read_total`          | Total read SysCalls to the kernel. /proc/[pid]/io syscr. <br><br>Type: counter                                                        | `server` |
| `minio_system_process_syscall_write_total`         | Total write SysCalls to the kernel. /proc/[pid]/io syscw. <br><br>Type: counter                                                       | `server` |

| `minio_node_scanner_versions_scanned`      | Total number of object versions scanned since server start. |
| `minio_node_syscall_read_total`            | Total read SysCalls to the kernel. /proc/[pid]/io syscr.    |
| `minio_node_syscall_write_total`           | Total write SysCalls to the kernel. /proc/[pid]/io syscw.   |
| `minio_usage_last_activity_nano_seconds`   | Time elapsed (in nano seconds) since last scan activity.    |

# Bucket Metrics

Linux containers run using the same Linux kernel of the host (machine, virtual machine, cloud server, etc). This just means that they are very lightweight (compared to full virtual machines emulating an entire operating system).