alerting: Address review

node/builder.go

@@ -28,6 +28,7 @@ import (
 	"go.uber.org/fx"
 	"golang.org/x/xerrors"
 
+	"github.com/filecoin-project/lotus/build"
 	"github.com/filecoin-project/lotus/chain/beacon"
 	"github.com/filecoin-project/lotus/chain/types"
 	"github.com/filecoin-project/lotus/extern/sector-storage/stores"
@@ -152,7 +153,7 @@ func defaults() []Option {
 		Override(new(journal.Journal), modules.OpenFilesystemJournal),
 		Override(new(*alerting.Alerting), alerting.NewAlertingSystem),
 
-		Override(CheckFDLimit, modules.CheckFdLimit(16<<10)),
+		Override(CheckFDLimit, modules.CheckFdLimit(build.DefaultFDLimit)),
 
 		Override(new(system.MemoryConstraints), modules.MemoryConstraints),
 		Override(InitMemoryWatchdog, modules.MemoryWatchdog),

node/builder_miner.go

@@ -15,6 +15,7 @@ import (
 	storage2 "github.com/filecoin-project/specs-storage/storage"
 
 	"github.com/filecoin-project/lotus/api"
+	"github.com/filecoin-project/lotus/build"
 	"github.com/filecoin-project/lotus/chain/gen"
 	"github.com/filecoin-project/lotus/chain/gen/slashfilter"
 	sectorstorage "github.com/filecoin-project/lotus/extern/sector-storage"
@@ -74,7 +75,7 @@ func ConfigStorageMiner(c interface{}) Option {
 	return Options(
 		ConfigCommon(&cfg.Common, enableLibp2pNode),
 
-		Override(CheckFDLimit, modules.CheckFdLimit(100_000)), // recommend at least 100k FD limit to miners
+		Override(CheckFDLimit, modules.CheckFdLimit(build.MinerFDLimit)), // recommend at least 100k FD limit to miners
 
 		Override(new(api.MinerSubsystems), modules.ExtractEnabledMinerSubsystems(cfg.Subsystems)),
 		Override(new(stores.LocalStorage), From(new(repo.LockedRepo))),

node/modules/alerts.go

@@ -7,13 +7,14 @@ import (
 
 func CheckFdLimit(min uint64) func(al *alerting.Alerting) {
 	return func(al *alerting.Alerting) {
-		if ulimit.GetLimit == nil {
+		soft, _, err := ulimit.GetLimit()
+
+		if err == ulimit.ErrUnsupported {
+			log.Warn("FD limit monitoring not available")
 			return
 		}
 
 		alert := al.AddAlertType("process", "fd-limit")
-
-		soft, _, err := ulimit.GetLimit()
 		if err != nil {
 			al.Raise(alert, map[string]string{
 				"message": "failed to get FD limit",