Any way to reach 100MB/s?

Hi. I’m using Syncthing to sync files from two computers in my local network (both connected with Cat6 cables via a switch). If I manually transfer files between the two computers, they transfer at about 100MB/s, but when using Syncthing, it seems capped at around 40-50MB/s (and even slower).

(I tried syncing the exact same test file that is 1GB to make sure the results are fair)

I wanted to know if that’s a limitation, or if there’s a way around it that I’m not aware of?


There is no artificial limitation. Are you sure the two devices are connected directly (i.e. not using relays or QUIC)? Screenshots from both sides showing the IP addresses would be useful.

Syncthing can also be limited by CPU when encrypting and decrypting the data. What kind of hardware are you using specifically?

Yes, they are connected directly with a switch. Transferring a file with a network share in Windows is around 100 MB/s. Addresses are and

I actually disabled compression in the Advanced tab, and one PC is with a Ryzen 5 3600 and the other with an 8th gen core i7, so no problem there I think.

Syncthing has multiple different protocols for connections. You need to provide screenshots for us to understand what type of protocol and type of connection its using.

Also, check cpu/disk utilization on both sides.

Happily, what part do I need to screenshot in Syncthing?

I will check cpu/disk, but I don’t think they are 100%.

The whole ui is best, with the folder and the remote device expanded.

First PC is The other PC is

When transferring the usage is not at 100% (more like 30%) so that’s not a bottleneck

What kind of files are you transferring? For large files it should be able to get close to max, for small-ish files it’s expected to take more time (overhead, fsync).

When transferring games, there are a lot of files so I guess 50-60 MB/s is pretty good. The thing is, the speed is the same when transferring one big file.

I don’t mind it much, the program is so good that I can absolutely live with it, just wondered if I’m doing something wrong maybe

I think if you try with a single multi-gigabyte file you’ll get close to the max. 10k files over 50gb means 5mb files on average, which means we spend quite a lot of time fsync’ing to prevent data loss.

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