Making Tailscale Faster

I wonder if the post's focus on Linux/Android is just because that's where they started, or because they're leveraging techniques that are only possible on Linux/Android?

• chrash · 10 hours ago

  it sounds like they’re leveraging Linux features that may not exist 1:1 on Darwin and NT

  • apenwarr · 6 hours ago

    (Tailscale cofounder) Yes, that’s most of it. Most packet-level optimizations are necessarily platform specific and this post was mostly about the linux dataplane. That said, the architectural multiqueue improvements and memory optimizations are useful starting points to build on for every platform.

Leaves them where they landed. Slop check : yes +++ATH

• api · 10 hours ago

  Also makes it sound like they were the first to do stuff like NAT traversal, which goes WAY back.

  • seabrookmx · 8 hours ago

    I like to think of them like Docker. None of Docker's functionality was new, they just wrapped it in a smooth enough DX for it to reach escape velocity.

In our use case latency went parabolic at 250 sessions pumping just 60 mb/s through a tunnel.

I would like less battery usage with exit node.

• nirav72 · 7 hours ago

  You’re using a battery powered device as an exit node?

  • zbentley · 1 hour ago

    No idea if this is what they meant, but it’s plausible that client battery usage goes up when connected to Tailscale using an exit node. Suddenly, a lot more traffic has to be processed in userland, on the CPU. Ordinary internet transit might be offloaded to the kernel or hardware such that it’s more battery-efficient. Then again, that begs the question of what you’re heavily using exit-node-routed internet links for that Tailscale’s battery draw is noticeable. Most network-intensive internet tasks draw way more power to drive whatever the application is, such that VPN overhead is a rounding error.

I used to LOVE tailscale. Then I put wireguard on my home network exposed to the internet with a dynamic DNS provider and it immediately became irrelevant. Not only is raw wireguard more stable (I don't have to fight the DNS issues on my mobile phones) it feels faster and is amazingly simple to set up.

• PorciiVorbesc · 9 hours ago

  Care to share your setup? I did some research into self hosting my own wireguard for my nuc and rpi, before ultimately settling on Tailscale because of how much simpler and plug-and-lay it was to add/remove devices compared to self hosting wireguard, not dealing with certificates, maintenance, etc.

  • davidee · 9 hours ago

    There are no certificates to share with Wireguard. Nothing to rotate if you don't want to. Once it works, it works. I've even got a backup wireguard server running on a Pi 1b. Works fine. We currently run wireguard on our router (and it seems more and more routers are supporting it). There are keys to configure for each client, but once you have the configuration for one client, the rest come very quickly and easily. I should add that I don't have any experience with Tailscale, but compared to OpenVPN and other VPN solutions, Wireguard is lightweight, simple, and easy to setup/configure. We use it on all our mobile devices (phones, laptops, tablets) to tunnel our traffic through our home network with all the filtering it offers (along side access to private services we host).

  • bmurphy1976 · 7 hours ago

    Get a Unifi system. It's built in. Works great!

  • havaloc · 6 hours ago

    I use an Island Router with Wireguard server built in, it handles DDNS and even the base Island router is beefy enough to give me up to 954mbps or so of Wireguard to right inside my home network. It took 2 minutes to set up. That being said, I do understand the appeal of Tailscale and have used it.

  • fitblipper · 3 hours ago

    I have an openwrt router running wireguard. I use it to provision the peer keys and routes. I also use openwrts cloudflare ddns which is super simple to setup. Any new client I want to add I jump into the wireguard interface in the GUI, go to the peer tab, and it does everything for me there.

• UltraSane · 8 hours ago

  My favorite thing about Tailscale is how it lets you SSH/RDP INTO servers without having to open any ports.

• tristanj · 6 hours ago

  Tailscale takes two minutes to setup and you can add more devices with zero configuration. WireGuard takes 30 mins to an hour to set up, you'll need to configure port forwarding, DDNS, create keys for each device, and add them to each device manually. But you have 100% control. Performance-wise, I haven't noticed a difference. My internet connection maxes out way before Tailscale hits any performance limits. Tailscale wins for convenience.

• kccqzy · 6 hours ago

  No you are being disingenuous if you think raw wireguard is amazingly simple to set up. Sure it is simpler than IPSec. But it’s absolutely not simpler than Tailscale. I migrated my raw Wireguard setup to Tailscale because after a few months without any tinkering I simply forget details of my setup. I’d rather outsource it to Tailscale.

• pammf · 2 hours ago

  It all depends on the use case…I have two raspberry units running as exit nodes back in my home country, one in my mother’s place and another in my in-laws’. They have regular internet providers routers, and at least one of the routers wouldn’t even be able to properly support port forwarding. Tailscale allowed me to setup everything at home and just plug them to their network in 5 mins.

• mnahkies · 2 hours ago

  I started with plain wireguard then migrated to tailscale, for my use case: - I was able to get my partner onto the tailnet by telling her to install an app and login. She doesn't know or care what wireguard is, but she can now access some of my self hosted services on her phone. - I'm able to easily dynamically register machines to the tailnet, such as CI jobs - I'm able to self host a DNS resolver and have it just work for devices connected to the tailnet I'm sure I could achieve these goals with plain wireguard, but I feel like I was able to outsource significant complexity to tailscale instead.

In my opinion, this is Tailscale's largest issue. It is slow. It cannot achieve speeds of greater than 1Gbps on clients systems (Windows & Mac), where you'd normally see it being used. On Linux, it struggles to achieve 10Gbps even when using a synthetic large packet benchmark [1]. With an IMIX benchmark, it would not be competitive whatsoever. This problem is fixable. WireGuard achieves higher performance (Kernel vs Userspace implementation) and IPsec implementations can achieve 100Gbps/400Gbps (DPDK/XDP). Zero-copy networking. From this blog post, I can say Tailscale still seems to not have the appetite for that, which is a shame. [1] https://tailscale.com/blog/more-throughput

• boomer_joe · 9 hours ago

  Yes. Just fucking stop doing userspace wireguard on linux https://github.com/tailscale/tailscale/issues/426 - issue has been open for 6 years (and is locked now, lol), btw. And if any tailscale employees are reading this - https://github.com/tailscale/tailscale/issues/15724 please fix this too. Regular users not using some sort of enterprise saas DNS (whatever their thing is?) deserve DNS privacy too.

  • iscoelho · 8 hours ago

    Tailscale's netstack is barely even WireGuard and they aren't compatible whatsoever. It's all marketing at this point. So it's not that simple: it's impossible for Tailscale to use any existing kernel or accelerated WireGuard implementation. They could derive inspiration, but a kernel module for Linux won't fix Windows & Mac. With that said, I feel they have enough funding to maintain a few platforms (:

  • apenwarr · 8 hours ago

    (Tailscale cofounder) That’s a good callout on DoH support, thanks. That said, note that if you run your own DNS server on your tailnet, the regular UDP DNS is automatically private because it’s carried over Tailscale. That’s the most common setup for non-SaaS DNS servers. DoH doesn’t really add anything in that arrangement. (And it’s more fiddly because you need to get and refresh a TLS cert.)

  • lokar · 8 hours ago

    Kernel networking is not automatically faster then userspace.

    • iscoelho · 7 hours ago

      You're correct, kernel isn't faster by default. With that said, the following is true: 1) the WireGuard kernel implementation, despite not even being zero-copy, exceeds the performance of the userspace implementation 2) implementations utilizing the userspace network stack have a maximum potential performance (context switch + memcpy is very slow, and that affects UDP disproportionately). It's the wrong approach for meaningful improvement.

      • vlovich123 · 2 hours ago

        Io_uring doesn’t have context switching and may not have memcpy. The trickier thing I suspect to get with wireguard is the encryption and GSO offload

        • iscoelho · 4 minutes ago

          That is not true unfortunately. io_uring only avoids the userspace copy/switch. There are many other copies in the Linux network stack.

  • TZubiri · 4 hours ago

    > Just fucking stop doing userspace wireguard on linux - issue has been open for 6 years If they would have taken that advice, tailscale instances would have been pwned by copy.fail

• TZubiri · 4 hours ago

  >(Kernel implementation) >IPsec Remember that at least one LPE CVE associated to kernel IPSec implementation has been discovered (copy.fail), which means that whatever gains you get from this vpn tunneling, is lost by breaking the basic user security system guarantee. You are better off not using a VPN at all rather than using kernel crypto

  • iscoelho · 2 minutes ago

    By that logic, we should avoid TCP as it's Linux kernel implementation has had plenty of CVEs. Thankfully we don't use that logic.

(Tailscale cofounder) I see a few comments here that using kernel wireguard would make it faster; it’s not really that simple. In fact, for a while (and we wrote a blog post about it), our optimizations made wireguard-go faster than kernel wireguard because it was better optimized. They adopted some of those improvements and now we’re on to the next order of magnitude together. For really high bandwidth cases, things like DPDK are the long term best choice and are primarily userspace, for good reasons. Kernel mode is not the pure benefit it once was (if it ever was). Separately, wireguard itself has a problem that the crypto suite it uses is not supported by hardware accelerators. So if we want to get into the hundreds of gigabits range, we will possibly need to switch packet formats entirely. (But, wireguard also needs to update to support post-quantum so maybe they’ll fix both problems at the same time and we can join in.)

• wahern · 7 hours ago

  Wireguard with PQ won't be Wireguard, anymore. It'll just be a rehash of IKE+IPsec. What made Wireguard better was the very simple handshake and minimal state, but no PQ algorithms can support that simplicity because the keys are too large and/or not as simple to use as ECC. Might as well switch to IPsec. Everything is already in place, including hardware acceleration. But most people won't, and we'll live in a world with duck-tape hacks built around a compromised Wireguard-ish layer.

  • apenwarr · 7 hours ago

    (Tailscale cofounder) I’m a little more optimistic; wireguard was always going to need a v2 eventually, that’s just the nature of cryptography. It’ll always be simpler than IPsec as long as it avoids live negotiation (you need to specify your suite up front for each node you talk to; v1 and v2 are the only suites) and continues to go over UDP instead of IPsec’s “it’s a different transport protocol!” madness. Things like Google’s PSP already achieve that while still being hardware acceleratable: https://github.com/google/psp Post-quantum negotiation will kinda suck but you don’t have to sacrifice everything.

    • Fordec · 6 hours ago

      Considering how core Wireguard is to the whole Tailscale value proposition, are they funding the future of that V2 roadmap on the open source side? If the answer is "no", and because the security world isn't going to stay put (particularly with AI math advancements happening lately are accelerating medium term risk), then one has to assume Tailscale is working on it's own in-house "V2" equivalent protocol for post-quantum support to enable that vision? I doubt you're doing nothing .

      • apenwarr · 6 hours ago

        (Tailscale cofounder) Nothing to announce yet, but yes, we absolutely do sponsor wireguard, with money and with code.

  • cyberax · 7 hours ago

    IPSec suffers from the "it can do everything" syndrome. Storytime: 15 years ago I co-founded a startup to build easy-to-use infrastructure management for AWS. At that time, it did not have cross-region VPC peering or routing, so you couldn't easily and safely have apps that communicate between regions. So I started working on creating an overlay network. My idea was to use IPsec, it even has an RFC that documents its kernel interface. So that when a host wants to send a packet to the secure network, the kernel goes to my userspace daemon, that in turn goes to the central server that provides it the key for the given host pair. And it turned out that the interface lacked a crucial part - on-demand key negotiation for incoming packets. It had this for _outgoing_ packets, but not incoming. The only sane way to make it work was to create a proactively updated database of all the hosts. Well, I did that. It also did not work (tm). I found so many issues with broken MTU handling, broken NAT traversal, etc. I eventually gave up on that idea and started working on a simple TUN/TAP-based overlay. I almost made everything work, but our startup got acquired by AWS, and this line of work was abandoned.

  • iscoelho · 7 hours ago

    IPsec is a terrible fit. Tailscale uses a control plane for peer & key distribution and renders almost all of the complexity in the IPsec protocol useless.

    • apenwarr · 7 hours ago

      (Tailscale cofounder) Many years ago I made a VPN for experimental purposes that kept IPsec’s data plane but abandoned IKE. It’s actually a pretty good arrangement and might be applicable here. My implementation relied on the extremely finicky Linux kernel IPsec and would never have worked in userspace macOS or windows. But yes, a Tailscale control plane with a per-node switchable data plane, one of which is IPsec with PQC, is a real option that would work. By locking down the control plane it becomes incompatible with classic IPsec, but also avoids most of the security gotchas that plagued IPsec.

      • iscoelho · 7 hours ago

        Yes, I agree, IPsec's complexity is definitely why client implementations are so universally finicky. That complexity is not needed by Tailscale.

      • cyberax · 6 hours ago

        > would never have worked in userspace macOS or windows It could have worked in macOS! It implements RFC-2367 (PF_KEY socket type) and I even made it work on my laptop. I traced the SA database operations on Windows, and it could have been done. Probably. But I abandoned that to preserve my sanity.

  • tptacek · 6 hours ago

    I don't think this really follows. Negotiation would be problematic, but you can just version the protocols and do WireGuard v1 and WireGuard v2, with v2 in a PQ configuration. As long as the configuration about which to use is static, you're not running up against the IPSEC problem. I don't think there's anything necessarily complicated about MLKEM that would make this too difficult. Switching to IPSEC loses you other WireGuard benefits; the wins don't end at "just one carefully curated set of cryptography primitives", but extend into things like DoS prevention and a design that admits to processing incoming frames without dynamic allocation.

  • rurban · 2 hours ago

    But then consider ipsec being backdoored by the NSA. As it came out of the Snowden leaks.

• sharktheone · 7 hours ago

  I always thought that just kernel mode makes it better. Didn't know that WG can't use hardware crypto accelerators. I hope it will someday

  • iscoelho · 7 hours ago

    It's only half the story. WireGuard uses chacha20-poly1305 and certain implementations can still achieve 100Gbps. Hardware acceleration is the path to 400Gbps and power efficiency though.

• 10000truths · 7 hours ago

  > But, wireguard also needs to update to support post-quantum It's quantum-resistant if you define a PSK. You still have to distribute the key out of band, but you already have to do that anyways for the public keys of the peers.

  • wisemang · 5 hours ago

    Why do public keys need to be distributed out of band?

    • 10000truths · 5 hours ago

      Because the public key is the identity in the Wireguard protocol. If Alice and Bob want to communicate with each other over Wireguard, then Alice has to know Bob's public key, and Bob has to know Alice's public key. If they don't already know each other's public keys, then that information has to be exchanged in a secure manner at least once, in order to prevent nosy Mallory from impersonating one of them. How can Alice and Bob exchange their public keys securely? Not with Wireguard, because they'd need to already know each other's public keys for that! So they need to use some other secure mechanism as a bootstrap. Hence, out of band distribution. In practice, Alice and Bob will often be two machines that are under control of the same entity, and that entity will transfer the key material from a third machine to the Alice and Bob machines over SSH or HTTPS. In those cases, the out of band mechanism is "SSH/HTTPS via trusted relay machine".

• iscoelho · 7 hours ago

  1) Besides marketing, I see no reason that Tailscale needs to concern itself with the WireGuard protocol spec at all. Tailscale is already incompatible. 2) Tailscale's control plane model for peer distribution avoids every concern affecting IPsec in regard to protocol negotiation security and compatibility. TL;DR, diverging from WireGuard & supporting AES (via protocol negotiation with hardware acceleration), would be relatively painless.

  • ignoramous · 2 hours ago

    > diverging from WireGuard You lose the formally-verified cryptography guarantees underpinning WireGuard & its implementation, though. That's a bigger tradeoff: https://www.wireguard.com/protocol/

    • iscoelho · 7 minutes ago

      Replacing ChaCha20 with AES-GCM does not change the cryptography guarantees of the WireGuard protocol whatsoever.

• lausobo · 7 hours ago

  Any chance the Apple TV can get a performance boost? Specially as an exit node. It always gives very little bandwidth. Thank you!

• ignoramous · 3 hours ago

  > wireguard itself has a problem that the crypto suite it uses is not supported by hardware accelerators. So if we want to get into the hundreds of gigabits range, we will possibly need to switch packet formats entirely Has hardware-offload (for AES et al) got faster still, or that keeping CPU busy in the data path for 100gbps workloads is not ideal, or something else? The WireGuard website claims ChaPoly is at least as fast as hardware-accelerated AES. And that it can be further sped up with SIMD. https://www.wireguard.com/known-limitations > now we’re on to the next order of magnitude together Curious: Is this work currently in progress? If so, what's more that's still lined up? The previous GRO/GSO(/LRO, too?) improvements were incredibly impressive (even to u/majke, https://news.ycombinator.com/item?id=35567268 ). Thanks.

  • mxey · 58 minutes ago

    > The WireGuard website claims ChaPoly is at least as fast as hardware-accelerated AES. I haven’t used WireGuard but I have easily doubled OpenSSH performance by switching back to AES.

• xingped · 2 hours ago

  Hey why do you hard code certain android apps to be excluded from Tailscale with split tunneling without giving users any way to disable split tunneling for these apps? It doesn't matter how you think VPN does or does not affect these apps, it's really awful anti-user behavior.

  • user3939382 · 1 hour ago

    I don’t trust or want tools from giant for profit corporations because there’s always some bullshit, and usually by the time you figure it out you’re out time or money. Never used Tailscale and this is a perfect example of my policy working. Notice the no response, they know what they’re doing and they don’t care. Layer 2 VPN is where it’s at anyway. I want to be on my LAN not managing one device or app at a time, I never got the wireguard hype.

    • close04 · 1 hour ago

      > Notice the no response, they know what they’re doing and they don’t care. I was with you in principle until this part. You gave them ~30 minutes before claiming "no answer".

      • user3939382 · 1 hour ago

        Fair let’s see.

      • tecleandor · 13 minutes ago

        Also, if Apenwarr is in Quebec, it was like 2am when he launched his question. He might be sleeping and all that ...

  • dobremeno · 53 minutes ago

    I haven't heard of this behavior before. Could you elaborate or link to some evidence of it?

  • alex7o · 18 minutes ago

    I think it is the opposite google allows some apps from opting out of VPN.

Re: Tailscale and speeds, I wish Tailscale had a better story about relay / DERP flexibility. Assume we have devices a, b and c, which are basically in different segments of the same network and have nice pings to each other. We're trying to ssh from a to c, but NAT traversal isn't possible. Both a and c can do NAT traversal to b. Instead of a going all the way over to the DERP in WAW and then back to c again, it could go a->b->c instead. In my experience, DERPs are pretty slow and have high latency (compared to not going off-network at all), but there's no real way to avoid them if everything you have is behind some sort of NAT, even if some of them are trivially traversable (think "devices can do UPNP").

• jaxxstorm · 40 minutes ago

  you appear to be describing a peer relay: https://tailscale.com/docs/features/peer-relay Note: I'm a tailscale employee

Please Tailscale don't get enshitified, I love you so much