# Copy speed (rsync between ZFS and UFS)



## arapaima (Oct 14, 2015)

I'm backing up files from a broken down system using a memstick and an additional harddrive.

- Three disks in a ZFS raidz pool which I've.
- One disk with a fresh UFS filesystem used for backing up files.

I'm using `rsync -avz` on a FreeBSD live CD for copying files to the UFS filesystem, but getting incredbly slow speeds. `zpool iostat` gives me reads around 7MB.

Is there any way of speeding up this process?


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## r_t_f_m (Oct 14, 2015)

And how *%busy* with `gstat` looks like ?


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## obsigna (Oct 14, 2015)

arapaima said:


> ... using `rsync -avz` ...
> Is there any way of speeding up this process?



Either remove the -z option or switch to a system with higher compression performance.


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## pboehmer (Oct 14, 2015)

You can lose the "z" (compression) option since you're syncing to a local drive.  My experience has been that compression works best over slower remote links.  If your `gstat` is not in the upper 90%, then you might want to try running multiple instances of `rsync` for different directories as opposed to using a single `rsync` instance for an entire filesystem.


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## arapaima (Oct 14, 2015)

`gstat` shows the drives to be quite stalled actually. Switching  rsync compression off did change it to around 20% though.
I'll give multiple instances of `rsync` a try. Thanks


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## Crivens (Oct 14, 2015)

Please also check for the memory statistics, maybe using top. If the ARC is pushed almost to non-existence, you will see these performance issues.


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## arapaima (Oct 14, 2015)

`top`


```
(...)
Mem: 118M Active, 4155M Intact, 3110M Wired, 114M Cache, 1530M Buf, 33M Free
ARC: 843M Total, 21M MFU, 621M MRU, 19M Anon, 26M Header, 157M Other
(...)
```

Running 7 instances of rsync at the moment. Seems like running several rsync instances and turning compression (-z) off speeded up the process.
I don't have any exact numbers for comparison though.


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