func (ls *libstore) GetList(key string) ([]string, error) { var args storagerpc.GetArgs var reply storagerpc.GetListReply args.Key = key args.WantLease = false args.HostPort = ls.hostport // FIRST CHECK FROM LOCAL CACHE!!! val, err := ls.leases.Get(key, &args) if err == nil { return val.([]string), nil } // CHECK IF WE NEED LEASE if ls.mode == Always { args.WantLease = true } else if ls.mode == Never { args.WantLease = false } // pick the right server cli, err := ls.GetServer(key) if err != nil { return nil, err } // call rpc to storage server err = cli.Call("StorageServer.GetList", &args, &reply) if err != nil { return nil, err } // check reply status if reply.Status != storagerpc.OK { err = GetErrorType(reply.Status) return nil, err } // check if allow lease if reply.Lease.Granted { ls.leases.Insert(key, reply.Value, reply.Lease) } return reply.Value, nil }
func (ls *libstore) Get(key string) (string, error) { var args storagerpc.GetArgs var reply storagerpc.GetReply //set wantlease to be false args.Key = key args.WantLease = false args.HostPort = ls.hostport // check if it is in cache val, err := ls.leases.Get(key, &args) if err == nil { return val.(string), nil } //CHECK IF WE NEED LEASE if ls.mode == Always { args.WantLease = true } else if ls.mode == Never { args.WantLease = false } // pick the right server cli, err := ls.GetServer(key) if err != nil { return "", err } // call rpc err = cli.Call("StorageServer.Get", &args, &reply) if err != nil { return "", err } if reply.Status != storagerpc.OK { err = GetErrorType(reply.Status) return "", err } // insert into cache if reply.Lease.Granted { ls.leases.Insert(key, reply.Value, reply.Lease) } return reply.Value, nil }
func (ls *libstore) GetList(key string) ([]string, error) { var args storagerpc.GetArgs var reply storagerpc.GetListReply args.Key = key args.WantLease = false args.HostPort = ls.hostport val, err := ls.localCache.Get(&args) if err == nil { return val.([]string), nil } if ls.mode == Always { args.WantLease = true } else if ls.mode == Never { args.WantLease = false } cli, err := ls.GetServer(key) if err != nil { return nil, err } err = cli.Call("StorageServer.GetList", &args, &reply) if err != nil { return nil, err } if reply.Status != storagerpc.OK { err = GetErrorType(reply.Status) return nil, err } if reply.Lease.Granted { ls.localCache.Put(key, reply.Value, reply.Lease) } return reply.Value, nil }
func (ls *libstore) GetList(key string) ([]string, error) { var args storagerpc.GetArgs var reply storagerpc.GetListReply current_time := time.Now().Unix() // Check whether the key is in the cache // If yes, return directly ls.list_cache_locker.Lock() if list_cache_elem, ok := ls.list_cache[key]; ok { if list_cache_elem.lease_end >= current_time { ls.list_cache_locker.Unlock() return list_cache_elem.content, nil } else { delete(ls.list_cache, key) } } ls.list_cache_locker.Unlock() args.Key = key args.HostPort = ls.host_port if ls.lease_mode == Normal { ls.list_cache_locker.Lock() if query_list, ok := ls.query_record[key]; ok { query_list.PushBack(current_time) } else { new_list := list.New() new_list.PushBack(current_time) ls.query_record[key] = new_list } if query_list, ok := ls.query_record[key]; ok { for elem := query_list.Front(); elem != nil; elem = elem.Next() { if elem.Value.(int64)+storagerpc.QueryCacheSeconds < current_time { query_list.Remove(elem) } else { break } } if query_list.Len() >= storagerpc.QueryCacheThresh { args.WantLease = true } else { args.WantLease = false } } ls.list_cache_locker.Unlock() } else if ls.lease_mode == Always { args.WantLease = true } target_server := ls.GetServerIndex(key) ls.rpc_connection[target_server].Call("StorageServer.GetList", args, &reply) if reply.Status != storagerpc.OK { return nil, errors.New("Error in Getlist") } if reply.Lease.Granted { ls.list_cache_locker.Lock() defer ls.list_cache_locker.Unlock() ls.list_cache[key] = &ListCacheElement{lease_end: time.Now().Unix() + int64(reply.Lease.ValidSeconds), content: reply.Value} } return reply.Value, nil }