Re: Blogbench results for HAMMER

[Michael Neumann <mneumann@xxxxxxxx>]

Matthew Dillon wrote:
>     I ran blockbench on a HAMMER partition and on a UFS partition and
>     got some rather interesting results.
>
>     I fully expected HAMMER's write performance to be bad compared to 
UFS,
>     because HAMMER is still double-buffering its data.  Indeed, as the
>     test began UFS seemed to be outdoing HAMMER.  But as the number 
of files
>     grew and the kernel started to have to recycle vnodes and 
buffers, UFS's
>     performance went completely to hell while HAMMER was able to 
maintain good
>     throughput.  Ths basic blog benchmark creates, reads, and writes 
around
>     20,000 files and goes for a lot of parallelism.
>
>     I don't know why UFS's write performance went to hell.. it pretty 
much
>     died completely after a very promising start.  But even ignoring that
>     as some sort of implementation fluke the read performance numbers 
speak
>     for themselves.
>
>     I haven't run bonnie++ yet.  I think UFS still does very well vs 
HAMMER
>     on saturated single-file I/O.

Would be nice to see some UFS benchmarks of FreeBSD, to make sure it's
not an issue with DragonFly's UFS "implementation". Too sad that I don't
have UFS anymore (only ZFS), so I could do it myself. And then, the
benchmark should be done on one and the same machine. But probably it's
wise to wait a few days for benchmarks :)

Regards,

  Michael