SOLVED Normal to see copy speed of 10 MiBps?

[rmont]

I am copying 2 TB of data from one disk to another (rsync job not attached to console).
They are both 5400 rpm SATA SMR devices.

I see a transfer speed of approximately 10 MiBps. Is this normal?

The server is not doing much else (CPU 2-3%). 16Gb RAM, core i3-9100.
It's a mix of 1K and 1-2M files.

 

[sretalla]

I see a transfer speed of approximately 10 MiBps

a mix of 1K and 1-2M files

Perfectly normal for high numbers of small files.

Lots of "wasted" time dealing with metadata, not a lot of time moving the actual data.

 

[rmont]

Thanks!

Roberto

 

[Chris Moore]

rsync

rsync is also a slow way to copy data. You can get much greater speed by using ZFS send and receive if you are sending a pool or dataset.

 

[Etorix]

SMR drives are also a plausible reason for poor sustained writes. Most importantly, you shouldn't be using SMR drives with ZFS.

 

[Chris Moore]

They are both 5400 rpm SATA SMR devices.
---
I see a transfer speed of approximately 10 MiBps. Is this normal?

The server is not doing much else (CPU 2-3%). 16Gb RAM, core i3-9100.
It's a mix of 1K and 1-2M files.

What model hard drives are you using?

These are just two single drives, not a pool of drives, right?

 

[sretalla]

SMR drives are also a plausible reason for poor sustained writes. Most importantly, you shouldn't be using SMR drives with ZFS.

I had somehow missed that point... indeed this may explain extreme slowness in large data transfer.

Please have a look at dmesg to see if your disks are struggling (but generally look at replacing them with CMR).