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Subject: Re: ZFS slow write performance
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Paul Mather wrote:

> Currently, I am just trying to rsync data locally from a read-only 
> UFS2-mounted USB-attached hard drive, and am getting (IMHO) poor write 
> speeds of only about 5 MiB/sec.  I can't figure out why this is so 
> relatively low.

> Any help or advice is appreciated.

There could be many reasons, but you will have to dig more to find them. 
For example, it might be just that USB has a greater latency and it 
interferes with some assumptions, but it's only a guess.

Try 8.0-BETA2, it has both new ZFS and new USB code.