Slow copying of file(s) over SMB and WebDAV performance impacted too

[NiKRuLeZ]

Hey all,

I’ve noticed something that doesn’t seem right. When I start copying a single large file (via SMB), the transfer begins very quickly, but this only lasts for around four to five minutes. After that, the speed drops sharply and eventually settles at around 600–700 kb/sec. This behaviour never used to occur – previously, file transfers remained fast throughout, and WebDAV connections held a steady, high data flow without any slowdown.

Setup:

• NAS model: QNAP TS-262

• NAS firmware: QTS 5.2.7.3297 (build 20251024)

• NAS → router: 1 Gbps link

• MacBook Pro M4 → router: 802.11ac 2×2 MIMO 5 GHz

• MacBook Pro M4 → NAS: SMB 3.1.1

I’ve attached screenshots showing that the drive is healthy, along with the network graph that illustrates the initial high speeds, followed by a sudden drop, and then a further decline.

I’ve also observed the same behaviour when using WebDAV for streaming a file to an HTPC, following the same pattern of an initially high rate that quickly falls away rendering the play-black unplayable at that point.

Any help on this would be really appreciated.

[dolbyman]

What disks are in the NAS and how are they set up ?

[NiKRuLeZ]

It’s only got 1 HDD currently installed without any RAID configuration.

[dolbyman]

To make sure it’s not the wifi, can you hard-wire into the network and test ?

The NAS should saturate 1GbE, even with a single drive (sequential read/write of large files)

[NiKRuLeZ]

Connected it via Ethernet and got a constant 116 MB/sec throughout the full 80 GB transfer (see screenshot)

[dolbyman]

Seems like a WiFi issue then

[NiKRuLeZ]

Some good news.

I restarted my router that had been on for the last 180 days, then tried to re-transfer that large file again and now it transferred over wi-fi at a constant rate of 74 MB/sec. Problem fixed by a simple router restart!

Thanks for nudging me in the right direction!

Problem fixed! Thanks for all the advice though!

[SteveKo]

Thanks so much for sharing both the problem and your solution!

We believe this will be incredibly helpful to other users who encounter similar issues in the future!