diff --git a/package.json b/package.json
index 1bd62e4..7b4cebd 100644
--- a/package.json
+++ b/package.json
@@ -71,6 +71,7 @@
     "mime-types": "^2.1.33",
     "nanoid": "^3.1.30",
     "obsidian": "^0.13.26",
+    "p-queue": "^7.2.0",
     "path-browserify": "^1.0.1",
     "process": "^0.11.10",
     "qrcode": "^1.5.0",
diff --git a/src/baseTypes.ts b/src/baseTypes.ts
index 6d25d82..e2c3ce4 100644
--- a/src/baseTypes.ts
+++ b/src/baseTypes.ts
@@ -57,6 +57,7 @@ export interface RemotelySavePluginSettings {
   vaultRandomID?: string;
   autoRunEveryMilliseconds?: number;
   agreeToUploadExtraMetadata?: boolean;
+  concurrency?: number;
 }
 
 export interface RemoteItem {
diff --git a/src/main.ts b/src/main.ts
index 0d2dc70..5156a71 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -54,6 +54,7 @@ const DEFAULT_SETTINGS: RemotelySavePluginSettings = {
   vaultRandomID: "",
   autoRunEveryMilliseconds: -1,
   agreeToUploadExtraMetadata: false,
+  concurrency: 5,
 };
 
 interface OAuth2Info {
@@ -230,6 +231,7 @@ export default class RemotelySavePlugin extends Plugin {
           deletions,
           (key: string) => self.trash(key),
           this.settings.password,
+          this.settings.concurrency,
           (i: number, totalCount: number, pathName: string, decision: string) =>
             self.setCurrSyncMsg(i, totalCount, pathName, decision)
         );
diff --git a/src/settings.ts b/src/settings.ts
index 23a0fa0..97aa9f3 100644
--- a/src/settings.ts
+++ b/src/settings.ts
@@ -521,6 +521,27 @@ export class RemotelySaveSettingTab extends PluginSettingTab {
           });
       });
 
+    const concurrencyDiv = generalDiv.createEl("div");
+    new Setting(concurrencyDiv)
+      .setName("Concurrency")
+      .setDesc(
+        "How many files do you want to download or upload in parallel at most?"
+      )
+      .addDropdown((dropdown) => {
+        dropdown.addOption("1", "1");
+        dropdown.addOption("2", "2");
+        dropdown.addOption("5", "5");
+        dropdown.addOption("10", "10");
+
+        dropdown
+          .setValue(`${this.plugin.settings.concurrency}`)
+          .onChange(async (val) => {
+            const realVal = parseInt(val);
+            this.plugin.settings.concurrency = realVal;
+            await this.plugin.saveSettings();
+          });
+      });
+
     //////////////////////////////////////////////////
     // below for general chooser (part 1/2)
     //////////////////////////////////////////////////
diff --git a/src/sync.ts b/src/sync.ts
index 219f54d..8abbae6 100644
--- a/src/sync.ts
+++ b/src/sync.ts
@@ -5,6 +5,7 @@ import {
   Vault,
   requireApiVersion,
 } from "obsidian";
+import PQueue from "p-queue";
 import {
   RemoteItem,
   SUPPORTED_SERVICES_TYPE,
@@ -891,10 +892,10 @@ export const doActualSync = async (
   deletions: DeletionOnRemote[],
   localDeleteFunc: any,
   password: string = "",
+  concurrency: number = 1,
   callbackSyncProcess?: any
 ) => {
   const mixedStates = syncPlan.mixedStates;
-  let i = 0;
   const totalCount = sortedKeys.length || 0;
 
   log.debug(`start syncing extra data firstly`);
@@ -907,41 +908,139 @@ export const doActualSync = async (
   );
   log.debug(`finish syncing extra data firstly`);
 
-  for (let i = 0; i < sortedKeys.length; ++i) {
-    const key = sortedKeys[i];
-    const val = mixedStates[key];
+  log.debug(`concurrency === ${concurrency}`);
+  if (concurrency === 1) {
+    // run everything in sequence
+    // good old way
+    for (let i = 0; i < sortedKeys.length; ++i) {
+      const key = sortedKeys[i];
+      const val = mixedStates[key];
 
-    log.debug(`start syncing "${key}" with plan ${JSON.stringify(val)}`);
+      log.debug(`start syncing "${key}" with plan ${JSON.stringify(val)}`);
 
-    if (callbackSyncProcess !== undefined) {
-      await callbackSyncProcess(i, totalCount, key, val.decision);
+      if (callbackSyncProcess !== undefined) {
+        await callbackSyncProcess(i, totalCount, key, val.decision);
+      }
+
+      await dispatchOperationToActual(
+        key,
+        vaultRandomID,
+        val,
+        client,
+        db,
+        vault,
+        localDeleteFunc,
+        password
+      );
+      log.debug(`finished ${key}`);
+    }
+  } else {
+    let realCounter = 0;
+
+    log.debug(`1. create all folders from shadowest to deepest`);
+    for (let i = sortedKeys.length - 1; i >= 0; --i) {
+      const key = sortedKeys[i];
+      const val = mixedStates[key];
+
+      if (val.decision === "skipFolder" || val.decision === "createFolder") {
+        log.debug(`start syncing "${key}" with plan ${JSON.stringify(val)}`);
+
+        if (callbackSyncProcess !== undefined) {
+          await callbackSyncProcess(realCounter, totalCount, key, val.decision);
+        }
+        realCounter += 1;
+
+        await dispatchOperationToActual(
+          key,
+          vaultRandomID,
+          val,
+          client,
+          db,
+          vault,
+          localDeleteFunc,
+          password
+        );
+        log.debug(`finished ${key}`);
+      }
     }
 
-    await dispatchOperationToActual(
-      key,
-      vaultRandomID,
-      val,
-      client,
-      db,
-      vault,
-      localDeleteFunc,
-      password
-    );
-    log.debug(`finished ${key}`);
+    log.debug(`2. delete files and folders from deepest to shadowest`);
+    for (let i = 0; i < sortedKeys.length; ++i) {
+      const key = sortedKeys[i];
+      const val = mixedStates[key];
+      if (
+        val.decision === "uploadLocalDelHistToRemoteFolder" ||
+        val.decision === "keepRemoteDelHistFolder"
+      ) {
+        log.debug(`start syncing "${key}" with plan ${JSON.stringify(val)}`);
 
-    // await Promise.all(
-    //   Object.entries(mixedStates).map(async ([k, v]) =>
-    //     dispatchOperationToActual(
-    //       k as string,
-    //       vaultRandomID,
-    //       v as FileOrFolderMixedState,
-    //       client,
-    //       db,
-    //       vault,
-    //       localDeleteFunc,
-    //       password
-    //     )
-    //   )
-    // );
+        if (callbackSyncProcess !== undefined) {
+          await callbackSyncProcess(realCounter, totalCount, key, val.decision);
+        }
+        realCounter += 1;
+
+        await dispatchOperationToActual(
+          key,
+          vaultRandomID,
+          val,
+          client,
+          db,
+          vault,
+          localDeleteFunc,
+          password
+        );
+        log.debug(`finished ${key}`);
+      }
+    }
+
+    log.debug(
+      `3. upload or download files in parallel, with the desired concurrency=${concurrency}`
+    );
+    const queue = new PQueue({ concurrency: concurrency, autoStart: true });
+
+    // const commands: any[] = [];
+
+    for (let i = 0; i < sortedKeys.length; ++i) {
+      const key = sortedKeys[i];
+      const val = mixedStates[key];
+      if (
+        val.decision === "skipUploading" ||
+        val.decision === "uploadLocalDelHistToRemote" ||
+        val.decision === "keepRemoteDelHist" ||
+        val.decision === "uploadLocalToRemote" ||
+        val.decision === "downloadRemoteToLocal"
+      ) {
+        const fn = async () => {
+          log.debug(`start syncing "${key}" with plan ${JSON.stringify(val)}`);
+
+          if (callbackSyncProcess !== undefined) {
+            await callbackSyncProcess(
+              realCounter,
+              totalCount,
+              key,
+              val.decision
+            );
+
+            realCounter += 1;
+          }
+
+          await dispatchOperationToActual(
+            key,
+            vaultRandomID,
+            val,
+            client,
+            db,
+            vault,
+            localDeleteFunc,
+            password
+          );
+
+          log.debug(`finished ${key}`);
+        };
+        queue.add(fn);
+      }
+    }
+
+    await queue.onIdle();
   }
 };