Telling syncthing to be more nice

Support
1

I’ve an i3-4130T CPU with 4 gigs of ram and an SSHD. I also have a thinkpad X220 with i5-2520M and the same. Not the fastest ones. Is there any way to tell syncthing not to be that aggressive with system resources? I just do the initial sync with ~ 200 gigs/13k files. I’m scared that initial sync will burn my desktop computer and thinkpad. I’ve no problem with if this would take a week (always-on). I know there is something like nice and ionice.

Edit: I can barely browse the web meanwhile, disk io must be somewhat high.

2

It already nice:s and ionice:s itself by default on Linux (which I guess you run but you don’t say).

3

Yes, I’m using linux. Can you tweak the nice values yourself? I want them to be as nice as possible :smiley: I don’t think it is an issue with CPU or RAM usage, when I look at htop it is quite “nice”. The bottleneck seems to be really disk io. I guess the initial scanning needs to read a lot from disk?

Screenshot_2018-05-30_13-41-51
Screenshot_2018-05-30_13-41-51728×438 80.3 KB

syncthing-cpu-linux-amd64-v0.14.47-133723.pprof (37.0 KB)

syncthing-heap-linux-amd64-v0.14.47-133725.pprof (150.5 KB)

4

It needs to read everything from disk for the scan as you’d expect… It’s one off.

5

If you REALLY want to limit/cap Syncthing’s storage bandwidth, your only option may be to use cgroups: https://andrestc.com/post/cgroups-io/

6

There’s also apparently four threads scanning. Adjust hashers (advanced config) down to 1 for each folder and, if you have more than one, pause some to limit concurrency.

1 Like
7

Thanks, I only have 1 folder to sync and the hashers setting is set to 0. Also found that really detailed description about hashers from you @calmh, thanks!

8

This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.