# Synthing opens a ton of threads to a point of resource exhaustion

**URL:** https://forum.syncthing.net/t/synthing-opens-a-ton-of-threads-to-a-point-of-resource-exhaustion/27114
**Category:** Support
**Created:** [September 9, 2026, 11:27pm UTC](https://forum.syncthing.net/t/synthing-opens-a-ton-of-threads-to-a-point-of-resource-exhaustion/27114 "2026-09-09T23:27:23Z")
**Posts on this page:** 5
**Page:** 1

<div class="post-metadata">

### Author: ![kuba-orlik](https://forum.syncthing.net/user_avatar/forum.syncthing.net/kuba-orlik/32/16059_2.png) [@kuba-orlik](https://forum.syncthing.net/u/kuba-orlik)
#### Post date: [September 9, 2026, 11:27pm UTC](https://forum.syncthing.net/t/synthing-opens-a-ton-of-threads-to-a-point-of-resource-exhaustion/27114/1 "2026-09-09T23:27:23Z")

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I’m seeing Synthing opening a ton of threads when scanning a directory. It’s an ever-growing list of threads:

```plaintext
syncthing@ansible1:/$ ps -eLf | grep 'yncthing' | wc -l
4523

```

My data dir is a JuiceFS Mount — not sure if that’s relevant.

I’ve set the config to limit resource usage. Copiers and hashers set to 1. copy\_file\_range enabled. `maxConcurrentIncomingRequestKiB` set to `32768`. `pullerMaxPendingKiB` set to `16384`. `progressUpdateIntervalS` set to `-1`. `numConnections` set to 1.

The list of threads just constantly grows it looks like maybe some jobs aren’t closed once they’re done?

Any help diagnosing the issue is greatly appreciated

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<div class="post-metadata">

### Author: ![marbens](https://forum.syncthing.net/user_avatar/forum.syncthing.net/marbens/32/18260_2.png) [@marbens](https://forum.syncthing.net/u/marbens)
#### Post date: [September 10, 2026, 2:20am UTC](https://forum.syncthing.net/t/synthing-opens-a-ton-of-threads-to-a-point-of-resource-exhaustion/27114/2 "2026-09-10T02:20:46Z")

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What Syncthing version are you running?

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<div class="post-metadata">

### Author: ![calmh](https://forum.syncthing.net/user_avatar/forum.syncthing.net/calmh/32/15311_2.png) [@calmh](https://forum.syncthing.net/u/calmh)
#### Post date: [September 10, 2026, 5:06am UTC](https://forum.syncthing.net/t/synthing-opens-a-ton-of-threads-to-a-point-of-resource-exhaustion/27114/3 "2026-09-10T05:06:49Z")

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Taking a support bundle would help clarify what’s going on.

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<div class="post-metadata">

### Author: ![kuba-orlik](https://forum.syncthing.net/user_avatar/forum.syncthing.net/kuba-orlik/32/16059_2.png) [@kuba-orlik](https://forum.syncthing.net/u/kuba-orlik)
#### Post date: [September 13, 2026, 4:54pm UTC](https://forum.syncthing.net/t/synthing-opens-a-ton-of-threads-to-a-point-of-resource-exhaustion/27114/4 "2026-09-13T16:54:29Z")

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> [@marbens](#):
>
> What Syncthing version are you running?

```plaintext
syncthing v1.29.5 "Gold Grasshopper" (go1.24.2 linux-amd64) debian@debian 2025-04-20 21:21:27 UTC

```

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<div class="post-metadata">

### Author: ![tomasz86](https://forum.syncthing.net/letter_avatar_proxy/v4/letter/t/96bed5/32.png) [@tomasz86](https://forum.syncthing.net/u/tomasz86)
#### Post date: [September 13, 2026, 5:07pm UTC](https://forum.syncthing.net/t/synthing-opens-a-ton-of-threads-to-a-point-of-resource-exhaustion/27114/5 "2026-09-13T17:07:48Z")

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I think you should try upgrading to the newest version of Syncthing 2.x and see what happens there first. Your version comes from April 2025, so it’s quite outdated, and lot has changed in the code since then.