Executor abstraction (#384)
This change adds a layer of abstraction over poolmgr. Poolmgr is now just one of the ways to turn a function into a service; other implementations will be added. The executor abstraction is a uniform API over all these implementations. * Executor layer added on top of pool manager * Removed the external server for executor * Minor changes to keep existing semantics as much possible * Separating the executor vs. poolmgr backend functionality and associated data members * Executor logic separated from Poolmgr backend completely, placeholder for new backend * Changed references to poolmgr in tests * Moved poolmgr to it's package, as a side effect moved Cache to its's package (was causing cyclical dependency) and had to make some data structures exposed outside package * Rebased from master and changed references to tpr -> crd * Executor layer added on top of pool manager * Executor logic separated from Poolmgr backend completely, placeholder for new backend * Changed podName to a generic objectReference in fscache (#391) Changed podName to a generic objectReference in function service cache implementation. * Moved poolmgr to it's package, as a side effect moved Cache to its's package (was causing cyclical dependency) and had to make some data structures exposed outside package * Rebased from master and changed references to tpr -> crd * Merged from master with latest changes * Removed stale executor service & deployment from previous merge * Addressed review comments, still testing some areas
This commit is contained in:
Vishal
@@ -0,0 +1,195 @@
|
||||
/*
|
||||
Copyright 2016 The Fission Authors.
|
||||
|
||||
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 executor
|
||||
|
||||
import (
|
||||
"log"
|
||||
"os"
|
||||
"sync"
|
||||
"time"
|
||||
|
||||
"github.com/dchest/uniuri"
|
||||
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
|
||||
|
||||
"github.com/fission/fission/cache"
|
||||
"github.com/fission/fission/crd"
|
||||
"github.com/fission/fission/executor/fscache"
|
||||
"github.com/fission/fission/executor/poolmgr"
|
||||
)
|
||||
|
||||
type (
|
||||
Executor struct {
|
||||
gpm *poolmgr.GenericPoolManager
|
||||
functionEnv *cache.Cache
|
||||
fissionClient *crd.FissionClient
|
||||
fsCache *fscache.FunctionServiceCache
|
||||
|
||||
requestChan chan *createFuncServiceRequest
|
||||
fsCreateWg map[string]*sync.WaitGroup
|
||||
}
|
||||
createFuncServiceRequest struct {
|
||||
funcMeta *metav1.ObjectMeta
|
||||
respChan chan *createFuncServiceResponse
|
||||
}
|
||||
|
||||
createFuncServiceResponse struct {
|
||||
funcSvc *fscache.FuncSvc
|
||||
err error
|
||||
}
|
||||
)
|
||||
|
||||
func MakeExecutor(gpm *poolmgr.GenericPoolManager, fissionClient *crd.FissionClient, fsCache *fscache.FunctionServiceCache) *Executor {
|
||||
executor := &Executor{
|
||||
gpm: gpm,
|
||||
functionEnv: cache.MakeCache(10*time.Second, 0),
|
||||
fissionClient: fissionClient,
|
||||
fsCache: fsCache,
|
||||
|
||||
requestChan: make(chan *createFuncServiceRequest),
|
||||
fsCreateWg: make(map[string]*sync.WaitGroup),
|
||||
}
|
||||
go executor.serveCreateFuncServices()
|
||||
return executor
|
||||
}
|
||||
|
||||
// All non-cached function service requests go through this goroutine
|
||||
// serially. It parallelizes requests for different functions, and
|
||||
// ensures that for a given function, only one request causes a pod to
|
||||
// get specialized. In other words, it ensures that when there's an
|
||||
// ongoing request for a certain function, all other requests wait for
|
||||
// that request to complete.
|
||||
func (executor *Executor) serveCreateFuncServices() {
|
||||
for {
|
||||
req := <-executor.requestChan
|
||||
m := req.funcMeta
|
||||
|
||||
// Cache miss -- is this first one to request the func?
|
||||
wg, found := executor.fsCreateWg[crd.CacheKey(m)]
|
||||
if !found {
|
||||
// create a waitgroup for other requests for
|
||||
// the same function to wait on
|
||||
wg := &sync.WaitGroup{}
|
||||
wg.Add(1)
|
||||
executor.fsCreateWg[crd.CacheKey(m)] = wg
|
||||
|
||||
// launch a goroutine for each request, to parallelize
|
||||
// the specialization of different functions
|
||||
go func() {
|
||||
fsvc, err := executor.createServiceForFunction(m)
|
||||
req.respChan <- &createFuncServiceResponse{
|
||||
funcSvc: fsvc,
|
||||
err: err,
|
||||
}
|
||||
delete(executor.fsCreateWg, crd.CacheKey(m))
|
||||
wg.Done()
|
||||
}()
|
||||
} else {
|
||||
// There's an existing request for this function, wait for it to finish
|
||||
go func() {
|
||||
log.Printf("Waiting for concurrent request for the same function: %v", m)
|
||||
wg.Wait()
|
||||
|
||||
// get the function service from the cache
|
||||
fsvc, err := executor.fsCache.GetByFunction(m)
|
||||
req.respChan <- &createFuncServiceResponse{
|
||||
funcSvc: fsvc,
|
||||
err: err,
|
||||
}
|
||||
}()
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func (executor *Executor) createServiceForFunction(m *metav1.ObjectMeta) (*fscache.FuncSvc, error) {
|
||||
log.Printf("[%v] No cached function service found, creating one", m.Name)
|
||||
|
||||
env, err := executor.getFunctionEnv(m)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
// Appropriate backend handles the service creation
|
||||
backend := os.Getenv("EXECUTOR_BACKEND")
|
||||
switch backend {
|
||||
case "DEPLOY":
|
||||
return nil, nil
|
||||
default:
|
||||
pool, err := executor.gpm.GetPool(env)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
// from GenericPool -> get one function container
|
||||
// (this also adds to the cache)
|
||||
log.Printf("[%v] getting function service from pool", m.Name)
|
||||
fsvc, err := pool.GetFuncSvc(m)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return fsvc, nil
|
||||
}
|
||||
}
|
||||
|
||||
func (executor *Executor) getFunctionEnv(m *metav1.ObjectMeta) (*crd.Environment, error) {
|
||||
var env *crd.Environment
|
||||
|
||||
// Cached ?
|
||||
result, err := executor.functionEnv.Get(crd.CacheKey(m))
|
||||
if err == nil {
|
||||
env = result.(*crd.Environment)
|
||||
return env, nil
|
||||
}
|
||||
|
||||
// Cache miss -- get func from controller
|
||||
f, err := executor.fissionClient.Functions(m.Namespace).Get(m.Name)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// Get env from metadata
|
||||
log.Printf("[%v] getting env", m)
|
||||
env, err = executor.fissionClient.Environments(f.Spec.Environment.Namespace).Get(f.Spec.Environment.Name)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// cache for future lookups
|
||||
executor.functionEnv.Set(crd.CacheKey(m), env)
|
||||
|
||||
return env, nil
|
||||
}
|
||||
|
||||
// StartExecutor Starts executor and the backend components that executor uses such as Poolmgr,
|
||||
// deploymgr and potential future backends
|
||||
func StartExecutor(fissionNamespace string, functionNamespace string, port int) error {
|
||||
fissionClient, kubernetesClient, _, err := crd.MakeFissionClient()
|
||||
if err != nil {
|
||||
log.Printf("Failed to get kubernetes client: %v", err)
|
||||
return err
|
||||
}
|
||||
|
||||
instanceID := uniuri.NewLen(8)
|
||||
poolmgr.CleanupOldPoolmgrResources(kubernetesClient, functionNamespace, instanceID)
|
||||
|
||||
fsCache := fscache.MakeFunctionServiceCache()
|
||||
gpm := poolmgr.MakeGenericPoolManager(
|
||||
fissionClient, kubernetesClient, fissionNamespace,
|
||||
functionNamespace, fsCache, instanceID)
|
||||
|
||||
api := MakeExecutor(gpm, fissionClient, fsCache)
|
||||
go api.Serve(port)
|
||||
|
||||
return nil
|
||||
}
|
||||
Reference in New Issue
Block a user