cfgen: disable senpai on host with rotational root disk

Summary:
1. adding a method to `Node` so that we can check if the root block device is ssd or not.
2. update oomd cfgen logic to disable senpai when root disk is hdd.

Differential Revision: D57678416

fbshipit-source-id: 1f69d94db7219201172f3b50e86b78ebadc4adf9

src/oomd/cfgen/src/cfgen.rs

@@ -16,7 +16,6 @@ fn oomd_json(node: &Node) -> json::JsonValue {
         HostType::OnDemand => od_json_config(&attrs),
         _ => default_json_config(&attrs),
     }
-    // TODO(chengxiong) add other templates
 }
 
 fn oomd_dropin(node: &Node) -> Dropin {
@@ -44,7 +43,6 @@ fn default_json_config(attrs: &ConfigParams) -> json::JsonValue {
     rulesets.push(rule_senpai_drop_in_ruleset(attrs));
     rulesets.push(rule_tw_container_drop_in_ruleset(attrs));
 
-    // TODO(chengxiong): add more rule sections
     json::object! {
       "rulesets": rulesets,
       "version": CONFIG_VERSION,
@@ -731,9 +729,8 @@ fn oomd2_oomd_restart_threshold() -> BTreeMap<String, OomdRestartThreshold> {
     }
 }
 
-fn on_ssd(_node: &Node) -> bool {
-    true
-    // TODO(chengxiong): add this logic https://fburl.com/code/dqdu7ves
+fn on_ssd(node: &Node) -> bool {
+    node.has_ssd_root()
 }
 
 fn io_latency_supported(_node: &Node) -> bool {
@@ -783,7 +780,7 @@ fn fbtax2_blacklisted_jobs(node: &Node) -> Vec<&'static str> {
 }
 
 fn senpai_targets(node: &Node) -> Option<String> {
-    if get_host_type(node) == HostType::TwShared {
+    if should_enable_senpai(node) {
         return Some(String::from(
             "system.slice,workload.slice/workload-wdb.slice,hostcritical.slice,workload.slice/workload-wdb.slice/*,hostcritical.slice/*",
         ));
@@ -816,13 +813,16 @@ fn disable_senpai_dropin(node: &Node) -> bool {
     false
 }
 
+fn should_enable_senpai(node: &Node) -> bool {
+    get_host_type(node) == HostType::TwShared && on_ssd(node)
+}
+
 fn get_host_type(node: &Node) -> HostType {
-    // TODO(chengxiong): add logic to determine host types.
-    if node.hostname_prefix() == "twshared".into() {
+    if node.hostname_prefix() == TWSHARED {
         return HostType::TwShared;
     }
 
-    if node.hostname_prefix() == "od".into() {
+    if node.hostname_prefix() == OD {
         return HostType::OnDemand;
     }
 

src/oomd/cfgen/test/cfgen_test_inputs/devvm.json

@@ -1,4 +1,4 @@
-@generated SignedSource<<a0b9ff8a6a1b096881c6f45b66fb9c8e>>
+@generated SignedSource<<fc0baf1e6e709eabf64b1a0cb966db9e>>
 @codegen-command arc cfgen update-inputs fb-oomd
 {
   "fqdn": "devvm3170.cln0.facebook.com",
@@ -45,7 +45,8 @@
         "driver": "virtio_net",
         "driver_version": "1.0.0",
         "firmware_version": "",
-        "bus_info": "0000:00:02.0"
+        "bus_info": "0000:00:02.0",
+        "speed_mbps": 0
       }
     }
   },

src/oomd/cfgen/test/cfgen_test_inputs/twshared_senpai_disabled.json

@@ -0,0 +1,97 @@
+@generated SignedSource<<4e1840d2c3dc9925b88a8f546af46041>>
+@codegen-command arc cfgen update-inputs fb-oomd
+{
+  "fqdn": "twshared44829.07.ash9.facebook.com",
+  "region": "east",
+  "clusterType": "SERVICE_GENERIC_NON_MEMCACHE",
+  "modelId": 333245,
+  "kernelRelease": "5.12.0-0_fbk13_clang_7455_gb24de3bdb045",
+  "serverType": "TYPE_VI_FEED",
+  "experiments": [],
+  "cpuArchitecture": "skylake",
+  "metalosRootfs": false,
+  "provisioningConfig": {
+    "ethtoolByInterface": {
+      "eth0": {
+        "maxChannelsCombined": 128,
+        "maxChannelsRx": 64,
+        "maxChannelsTx": 64
+      }
+    },
+    "cpuCoreCount": 40,
+    "parentModelId": 336939,
+    "recoveryEnvironment": false,
+    "deviceType": "SERVER",
+    "datacenter": "ash9",
+    "cluster": "07",
+    "memTotal": 270023245824,
+    "osVersion": {
+      "distribution_name": "CentOS Stream release",
+      "version": 9,
+      "is_in_ramdisk": false,
+      "is_metalos": false
+    },
+    "pciByAddress": {
+      "0000:5e:00.0": {
+        "vendor_id": 5348,
+        "device_id": 5833,
+        "class_code": 131072,
+        "board_part_number": "BCM957302M3023CBK"
+      }
+    },
+    "static_smc_tiers": [],
+    "machine": "x86_64"
+  },
+  "bootConfig": {
+    "ethtoolByInterface": {
+      "eth0": {
+        "driver": "bnxt_en",
+        "driver_version": "5.12.0-0_fbk13_clang_7455_gb24d",
+        "firmware_version": "20.6.167.0/pkg 20.6.4.12",
+        "bus_info": "0000:5e:00.0"
+      }
+    }
+  },
+  "runtimeConfig": {
+    "hasHighPrivCert": true,
+    "regionRoutableCluster": "ash9.02",
+    "block_devices": {
+      "block_devices": {
+        "nvme0n1": {
+          "size_bytes": 1800360124416,
+          "is_rotational": false,
+          "model": "SAMSUNG MZ1LB1T9HALS-000FB",
+          "serial": "S4JTNA0M941126",
+          "physical_block_size": 4096,
+          "logical_block_size": 4096,
+          "is_root": false
+        },
+        "sda": {
+          "size_bytes": 2000398934016,
+          "is_rotational": true,
+          "model": "ST2000NM0008-2F3100",
+          "serial": "ZDS16SA4",
+          "physical_block_size": 512,
+          "logical_block_size": 512,
+          "is_root": true
+        }
+      }
+    },
+    "dynamic_smc_tiers": [],
+    "cluster_state": "CLUSTER_IN_USE",
+    "installed_platforms": [
+      "platform009",
+      "platform010",
+      "platform010-aarch64",
+      "platform010-compat"
+    ],
+    "device_nics_enum": [
+      "ETH0",
+      "SVC0"
+    ]
+  },
+  "reservationConfig": {
+    "active_machine_materialization_id": "6321b66383934",
+    "current_reservation_host_profile_id": "COMMON:NO_CPU_CONTROLLER|KERNEL:kernel_5.12.0-0_fbk13_clang_7455_gb24de3bdb045_base.v8|STORAGE:XFS_FULL|RUNTIME:DATASTORES_GENERIC_SYSCTLS|KERNEL_ARGS:kargs_default.v2|KERNEL_POLICY:KERNEL_POLICY_DATABASES|BOOT_CONFIG:bootloader814_initrd230_swap16G_native_arch"
+  }
+}