minio/cmd/healthcheck-handler.go
Harshavardhana 07a556a10b Avoid ListBuckets() call instead rely on simple HTTP GET (#8475)
This is to avoid making calls to backend and requiring
gateways to allow permissions for ListBuckets() operation
just for Liveness checks, we can avoid this and make
our liveness checks to be more performant.
2019-11-01 16:58:10 -07:00

115 lines
3.8 KiB
Go

/*
* MinIO Cloud Storage, (C) 2018 MinIO, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package cmd
import (
"fmt"
"net/http"
"os"
"runtime"
xhttp "github.com/minio/minio/cmd/http"
"github.com/minio/minio/cmd/logger"
)
const (
minioHealthGoroutineThreshold = 10000
)
// ReadinessCheckHandler -- checks if there are more than threshold
// number of goroutines running, returns service unavailable.
//
// Readiness probes are used to detect situations where application
// is under heavy load and temporarily unable to serve. In a orchestrated
// setup like Kubernetes, containers reporting that they are not ready do
// not receive traffic through Kubernetes Services.
func ReadinessCheckHandler(w http.ResponseWriter, r *http.Request) {
if err := goroutineCountCheck(minioHealthGoroutineThreshold); err != nil {
writeResponse(w, http.StatusServiceUnavailable, nil, mimeNone)
return
}
writeResponse(w, http.StatusOK, nil, mimeNone)
}
// LivenessCheckHandler -- checks if server can reach its disks internally.
// If not, server is considered to have failed and needs to be restarted.
// Liveness probes are used to detect situations where application (minio)
// has gone into a state where it can not recover except by being restarted.
func LivenessCheckHandler(w http.ResponseWriter, r *http.Request) {
ctx := newContext(r, w, "LivenessCheckHandler")
objLayer := globalObjectAPI
// Service not initialized yet
if objLayer == nil || globalSafeMode {
// Respond with 200 OK while server initializes to ensure a distributed cluster
// is able to start on orchestration platforms like Docker Swarm.
// Refer https://github.com/minio/minio/issues/8140 for more details.
// Make sure to add server not initialized status in header
w.Header().Set(xhttp.MinIOServerStatus, "server-not-initialized")
writeSuccessResponseHeadersOnly(w)
return
}
if !globalIsXL && !globalIsDistXL {
s := objLayer.StorageInfo(ctx)
if s.Backend.Type == BackendGateway {
if !s.Backend.GatewayOnline {
writeResponse(w, http.StatusServiceUnavailable, nil, mimeNone)
return
}
writeResponse(w, http.StatusOK, nil, mimeNone)
return
}
}
// For FS and Erasure backend, check if local disks are up.
var totalLocalDisks int
var erroredDisks int
for _, endpoint := range globalEndpoints {
// Check only if local disks are accessible, we do not have
// to reach to rest of the other servers in a distributed setup.
if endpoint.IsLocal {
totalLocalDisks++
// Attempt a stat to backend, any error resulting
// from this Stat() operation is considered as backend
// is not available, count them as errors.
if _, err := os.Stat(endpoint.Path); err != nil {
logger.LogIf(ctx, err)
erroredDisks++
}
}
}
// If all exported local disks have errored, we simply let kubernetes
// take us down.
if totalLocalDisks == erroredDisks {
writeResponse(w, http.StatusServiceUnavailable, nil, mimeNone)
return
}
writeResponse(w, http.StatusOK, nil, mimeNone)
}
// checks threshold against total number of go-routines in the system and
// throws error if more than threshold go-routines are running.
func goroutineCountCheck(threshold int) error {
count := runtime.NumGoroutine()
if count > threshold {
return fmt.Errorf("too many goroutines (%d > %d)", count, threshold)
}
return nil
}