diff --git a/.config/example.yml b/.config/example.yml
index e99323bb1c..9907925977 100644
--- a/.config/example.yml
+++ b/.config/example.yml
@@ -101,11 +101,11 @@ autoAdmin: true
 # Number of worker processes
 #clusterLimit: 1
 
-# Job concurrency per worker
+# Job concurrency per worker (Default: deliver=cpu x 8, inbox=cpu x 1)
 # deliverJobConcurrency: 128
 # inboxJobConcurrency: 16
 
-# Job rate limiter
+# Job rate limiter (Default: nolimit, 変更しないことを推奨)
 # deliverJobPerSec: 128
 # inboxJobPerSec: 16
 
diff --git a/src/queue/index.ts b/src/queue/index.ts
index 7638745fd8..91213f10c0 100644
--- a/src/queue/index.ts
+++ b/src/queue/index.ts
@@ -13,6 +13,7 @@ import { DriveFile } from '../models/entities/drive-file';
 import { getJobInfo } from './get-job-info';
 import { IActivity } from '../remote/activitypub/type';
 import { dbQueue, deliverQueue, inboxQueue, objectStorageQueue } from './queues';
+import { cpus } from 'os';
 
 function renderError(e: Error): any {
 	return {
@@ -27,6 +28,9 @@ const inboxLogger = queueLogger.createSubLogger('inbox');
 const dbLogger = queueLogger.createSubLogger('db');
 const objectStorageLogger = queueLogger.createSubLogger('objectStorage');
 
+export const deliverJobConcurrency = config.deliverJobConcurrency || ((cpus().length || 4) * 8);
+export const inboxJobConcurrency = config.inboxJobConcurrency || ((cpus().length || 4) * 1);
+
 deliverQueue
 	.on('waiting', (jobId) => deliverLogger.debug(`waiting id=${jobId}`))
 	.on('active', (job) => deliverLogger.debug(`active ${getJobInfo(job, true)} to=${job.data.to}`))
@@ -207,8 +211,8 @@ export function createCleanRemoteFilesJob() {
 
 export default function() {
 	if (!envOption.onlyServer) {
-		deliverQueue.process(config.deliverJobConcurrency || 128, processDeliver);
-		inboxQueue.process(config.inboxJobConcurrency || 16, processInbox);
+		deliverQueue.process(deliverJobConcurrency, processDeliver);
+		inboxQueue.process(inboxJobConcurrency, processInbox);
 		processDb(dbQueue);
 		procesObjectStorage(objectStorageQueue);
 	}
@@ -219,9 +223,11 @@ export function destroy() {
 		deliverLogger.succ(`Cleaned ${jobs.length} ${status} jobs`);
 	});
 	deliverQueue.clean(0, 'delayed');
+	deliverQueue.clean(0, 'wait');
 
 	inboxQueue.once('cleaned', (jobs, status) => {
 		inboxLogger.succ(`Cleaned ${jobs.length} ${status} jobs`);
 	});
 	inboxQueue.clean(0, 'delayed');
+	inboxQueue.clean(0, 'wait');
 }
diff --git a/src/queue/queues.ts b/src/queue/queues.ts
index ea5f6cf682..28fdc0730a 100644
--- a/src/queue/queues.ts
+++ b/src/queue/queues.ts
@@ -2,7 +2,7 @@ import config from '../config';
 import { initialize as initializeQueue } from './initialize';
 import { DbJobData, DeliverJobData, InboxJobData, ObjectStorageJobData } from './types';
 
-export const deliverQueue = initializeQueue<DeliverJobData>('deliver', config.deliverJobPerSec || 128);
-export const inboxQueue = initializeQueue<InboxJobData>('inbox', config.inboxJobPerSec || 16);
+export const deliverQueue = initializeQueue<DeliverJobData>('deliver', config.deliverJobPerSec || -1);
+export const inboxQueue = initializeQueue<InboxJobData>('inbox', config.inboxJobPerSec || -1);
 export const dbQueue = initializeQueue<DbJobData>('db');
 export const objectStorageQueue = initializeQueue<ObjectStorageJobData>('objectStorage');