Prepare, configure, and manage Firecracker microVMs in seconds!
virtualization
linux
microvm
firecracker
add --vcpu and --memory options
+42
-9
+1
Cargo.lock
+1
Cargo.lock
+1
crates/firecracker-up/Cargo.toml
+1
crates/firecracker-up/Cargo.toml
+3
-1
crates/firecracker-up/src/cmd/up.rs
+3
-1
crates/firecracker-up/src/cmd/up.rs
···
12
12
pub alpine: Option<bool>,
13
13
pub ubuntu: Option<bool>,
14
14
pub nixos: Option<bool>,
15
+
pub vcpu: u16,
16
+
pub memory: u16,
15
17
}
16
18
17
19
impl Into<Distro> for UpOptions {
···
44
46
}
45
47
46
48
firecracker_prepare::prepare(options.clone().into())?;
47
-
firecracker_vm::setup(options.into())?;
49
+
firecracker_vm::setup(options.clone().into(), options.vcpu, options.memory)?;
48
50
Ok(())
49
51
}
50
52
+25
crates/firecracker-up/src/main.rs
+25
crates/firecracker-up/src/main.rs
···
38
38
.arg(arg!(--alpine "Prepare Alpine rootfs").default_value("false"))
39
39
.arg(arg!(--nixos "Prepare NixOS rootfs").default_value("false"))
40
40
.arg(arg!(--ubuntu "Prepare Ubuntu rootfs").default_value("true"))
41
+
.arg(arg!(--vcpu <n> "Number of vCPUs"))
42
+
.arg(arg!(--memory <m> "Memory size in MiB"))
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.about("Start Firecracker MicroVM"),
42
44
)
43
45
.subcommand(Command::new("down").about("Stop Firecracker MicroVM"))
···
58
60
.arg(arg!(--alpine "Prepare Alpine rootfs").default_value("false"))
59
61
.arg(arg!(--nixos "Prepare NixOS rootfs").default_value("false"))
60
62
.arg(arg!(--ubuntu "Prepare Ubuntu rootfs").default_value("true"))
63
+
.arg(arg!(--vcpu <n> "Number of vCPUs"))
64
+
.arg(arg!(--memory <m> "Memory size in MiB"))
61
65
}
62
66
63
67
fn main() -> Result<()> {
···
65
69
66
70
match matches.subcommand() {
67
71
Some(("up", args)) => {
72
+
let vcpu = matches
73
+
.get_one::<String>("vcpu")
74
+
.map(|s| s.parse::<u16>().unwrap())
75
+
.unwrap_or(num_cpus::get() as u16);
76
+
let memory = matches
77
+
.get_one::<String>("memory")
78
+
.map(|s| s.parse::<u16>().unwrap())
79
+
.unwrap_or(512);
68
80
let options = UpOptions {
69
81
debian: args.get_one::<bool>("debian").copied(),
70
82
alpine: args.get_one::<bool>("alpine").copied(),
71
83
ubuntu: args.get_one::<bool>("ubuntu").copied(),
72
84
nixos: args.get_one::<bool>("nixos").copied(),
85
+
vcpu,
86
+
memory,
73
87
};
74
88
up(options)?
75
89
}
···
86
100
let alpine = matches.get_one::<bool>("alpine").copied().unwrap_or(false);
87
101
let nixos = matches.get_one::<bool>("nixos").copied().unwrap_or(false);
88
102
let ubuntu = matches.get_one::<bool>("ubuntu").copied().unwrap_or(false);
103
+
let vcpu = matches
104
+
.get_one::<String>("vcpu")
105
+
.map(|s| s.parse::<u16>().unwrap())
106
+
.unwrap_or(num_cpus::get() as u16);
107
+
let memory = matches
108
+
.get_one::<String>("memory")
109
+
.map(|s| s.parse::<u16>().unwrap())
110
+
.unwrap_or(if nixos { 2048 } else { 512 });
111
+
89
112
let options = UpOptions {
90
113
debian: Some(debian),
91
114
alpine: Some(alpine),
92
115
ubuntu: Some(ubuntu),
93
116
nixos: Some(nixos),
117
+
vcpu,
118
+
memory,
94
119
};
95
120
up(options)?
96
121
}
+10
-6
crates/firecracker-vm/src/firecracker.rs
+10
-6
crates/firecracker-vm/src/firecracker.rs
···
8
8
9
9
const NIXOS_BOOT_ARGS: &str = "init=/nix/store/pq529c6dd6x5vaxak4vpyxrv17ydvnwr-nixos-system-nixos-firecracker-25.05.802216.55d1f923c480/init root=/dev/vda ro console=ttyS0 reboot=k panic=1";
10
10
11
-
pub fn configure(logfile: &str, kernel: &str, rootfs: &str, arch: &str) -> Result<()> {
11
+
pub fn configure(
12
+
logfile: &str,
13
+
kernel: &str,
14
+
rootfs: &str,
15
+
arch: &str,
16
+
vcpu: u16,
17
+
memory: u16,
18
+
) -> Result<()> {
12
19
configure_logger(logfile)?;
13
20
setup_boot_source(kernel, arch, rootfs.contains("nixos"))?;
14
21
setup_rootfs(rootfs)?;
15
22
setup_network_interface()?;
16
-
setup_vcpu_and_memory(
17
-
num_cpus::get(),
18
-
if rootfs.contains("nixos") { 2048 } else { 512 },
19
-
)?;
23
+
setup_vcpu_and_memory(vcpu, memory)?;
20
24
21
25
// Wait before starting instance
22
26
sleep(Duration::from_millis(15));
···
160
164
Ok(())
161
165
}
162
166
163
-
fn setup_vcpu_and_memory(n: usize, memory: usize) -> Result<()> {
167
+
fn setup_vcpu_and_memory(n: u16, memory: u16) -> Result<()> {
164
168
println!("[+] Setting vCPU and memory...");
165
169
let payload = json!({
166
170
"vcpu_count": n,
+2
-2
crates/firecracker-vm/src/lib.rs
+2
-2
crates/firecracker-vm/src/lib.rs
···
12
12
mod guest;
13
13
mod network;
14
14
15
-
pub fn setup(distro: Distro) -> Result<()> {
15
+
pub fn setup(distro: Distro, vcpu: u16, memory: u16) -> Result<()> {
16
16
let app_dir = get_config_dir().with_context(|| "Failed to get configuration directory")?;
17
17
18
18
let logfile = format!("{}/firecracker.log", app_dir);
···
73
73
let arch = command::run_command("uname", &["-m"], false)?.stdout;
74
74
let arch = String::from_utf8_lossy(&arch).trim().to_string();
75
75
network::setup_network()?;
76
-
firecracker::configure(&logfile, &kernel, &rootfs, &arch)?;
76
+
firecracker::configure(&logfile, &kernel, &rootfs, &arch, vcpu, memory)?;
77
77
78
78
if !rootfs.contains("nixos") {
79
79
guest::configure_guest_network(&key_name)?;