apiclient/apiserver: add ephemeral-storage commands

[tzneal]

Issue number:

Closes #

Description of changes:

Adds apiclient/apiserver commands for initializing ephemeral storage and binding directories to that storage

Testing done:

Updated containerd package to run the new apiclient commands:

diff --git a/packages/containerd/containerd.service b/packages/containerd/containerd.service
index fc18c2ba..e483c3c1 100644
--- a/packages/containerd/containerd.service
+++ b/packages/containerd/containerd.service
@@ -9,6 +9,8 @@ Slice=runtime.slice
 EnvironmentFile=/etc/network/proxy.env
 EnvironmentFile=-/etc/containerd/nvidia.env
 ExecStart=/usr/bin/containerd
+ExecStartPre=apiclient ephemeral-storage init
+ExecStartPre=apiclient ephemeral-storage bind --dirs /var/lib/containerd /var/lib/kubelet /var/log/pods
 Type=notify
 Delegate=yes
 KillMode=process

I then launched an instance with 0 ephemeral disks, 1 disk, and multiple disks and ensured they all started up correctly. For the instance with > 0 disks, I ensured that our disk was faster:

bash-5.1# cd /var/log/pods
bash-5.1# dd if=/dev/zero of=./test bs=512k count=4096 oflag=direct
cd4096+0 records in
4096+0 records out
2147483648 bytes (2.1 GB, 2.0 GiB) copied, 1.50426 s, 1.4 GB/s

bash-5.1# cd /var/log
bash-5.1# dd if=/dev/zero of=./test bs=512k count=4096 oflag=direct
4096+0 records in
4096+0 records out
2147483648 bytes (2.1 GB, 2.0 GiB) copied, 18.6687 s, 115 MB/s

Terms of contribution:

By submitting this pull request, I agree that this contribution is dual-licensed under the terms of both the Apache License, version 2.0, and the MIT license.

[bcressey]

Nice, thanks for contributing this!