Hi,
for the last couple of days, Syncthing has been taking ages to sync even a simple small file under 5 MB to another server.
Both servers have stable 1 Gbit upload and download connections.
Is this a known issue with the current version? With the previous version, we had no issues for several months.
Best regards
FWIW, I’m not seeing these symptoms.
Thanks for your reply. How many files you dealing?
We have atm. around 250. Syncthing has only todo less syncs, sometimes 2-3 files sametime, but in general only 1 per minuite.
I’m thinking about to downgrade because we didn’t had this issues before and nothing else is changed.
About 170K files, almost 900 GiB.
Okay, very strange. Whats your timer for a fullscan in your shared folder?
I’m using 3s in general but put it now to 5s.Maybe too aggressive?
Is file watching disabled? If not, then there should be no reason to use such a low scan interval. Even if file watching is disabled or not working for some reason, the default scan interval in such a case is automatically set to 60s for a reason. If you use a very low value like 3s or 5s, this will make the folder being scanned constantly, just wasting resources.
In this regard, each of my Folders are configured the same: Watch for Changes is turned on, with the Full Rescan Interval set to 3600 seconds.
thanks for your anders!
@tomasz86 afaik i remember i choosed the low value because the “on-demand / filewatcher” was slow on windows server 2025. So i changed to 3s or now 5s. So you mean thats not necesarry? Then i will it with maybe 30sec.
@chaos Were i can check watcher settings? I’m using win-server 2025 standard.
Tested it quickly. Thats very slow. File sync needs between 5-15sec. Thats too long. I need it almost instantly if this is possible. How i can improve the watcher?
For each Folder’s settings is on the Advanced tab. It’s called Watch for Changes.
You can tweak the watcher delay in the Advanced Configuration (see https://docs.syncthing.net/users/config.html#config-option-folder.fswatcherdelays). Please keep in mind that deletions are further delayed by 6 times (e.g. if you set the watcher delay to 1s, deletions will be delayed by 6s, etc.).
Yes, but you need to go down into per-folder settings. If you want instant synchronisation, you can set the watcher to a value like 0.1. Please keep in mind that there will be some performance impact when using such low values.
thank you so much. Didn’t saw that before. 2s was still to slow. Sometimes the watcher/sync needs over 5sec.
I changed now to 1s which looks good so far. Performance is still not that good since ~1-2weeks. Bandwith is stable and 1GBit each server (3 in the cluster).
Will oberserve a bit this week and let you know. Thanks!
It looks good so far. Oberserving the performance atm with 1s.
Are you guys sure, that values e.g. like 1,5 is allowed for Fs Watcher Delay (seconds) ?
Yes, but with a dot, e.g. 1.5. The main use case is to set it to very small values like 0.1 for instantaneous sync.
As programmer i was trying with dot but it return back to comma o.O
Can you share a screenshot?
