From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.zx2c4.com (lists.zx2c4.com [165.227.139.114]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 69A48C433F5 for ; Mon, 21 Feb 2022 19:02:02 +0000 (UTC) Received: by lists.zx2c4.com (OpenSMTPD) with ESMTP id 0040284b; Mon, 21 Feb 2022 18:53:28 +0000 (UTC) Received: from isrv.corpit.ru (isrv.corpit.ru [86.62.121.231]) by lists.zx2c4.com (OpenSMTPD) with ESMTPS id 3d3ce569 (TLSv1.3:AEAD-AES256-GCM-SHA384:256:NO) for ; Mon, 21 Feb 2022 18:53:27 +0000 (UTC) Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id EF0F64062C; Mon, 21 Feb 2022 21:53:27 +0300 (MSK) Received: from [192.168.177.130] (mjt.wg.tls.msk.ru [192.168.177.130]) by tsrv.corpit.ru (Postfix) with ESMTP id C2D4511A; Mon, 21 Feb 2022 21:51:25 +0300 (MSK) Message-ID: Date: Mon, 21 Feb 2022 21:53:26 +0300 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.6.0 Subject: Re: WireGuard Windows should have default MTU of 1280. Content-Language: en-US To: Rujbin , "wireguard@lists.zx2c4.com" References: From: Michael Tokarev In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: wireguard@lists.zx2c4.com X-Mailman-Version: 2.1.30rc1 Precedence: list List-Id: Development discussion of WireGuard List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: wireguard-bounces@lists.zx2c4.com Sender: "WireGuard" 19.02.2022 04:23, Rujbin wrote: > Hello, > > i am just confused. When i use default MTU the Performance on Windows is VERY poor. It is almost unuseable. It happens on multiple Windows devices. I started using MTU 1280 for a while, but why is it only Windows with that issue? First, the speed is limited to 100mbps maximum. Thats weird, when i use MTU 1280 i have 1gbps. https://i.imgur.com/ELGOWDQ.png In our case with default MTU (of 1420 iirc), in-tunnel performance is near the direct pefrormance. When lowering MTU to 1280, the speed reduces a bit but not much (I guess due to larger overhead due to smaller packet size). > This bug exists for a long time to me. I ran Wireguard on almost every provider, (i didnt check if it happens on Azure) but this bug exists on Hetzner, DigitalOcean, OVH. This is not normal. I am running the latest stable version of Wireguard Windows. Kernel module on servers and BoringTun. I don't see a bug here. /mjt