Execution time of bonnie++

Having recently discovered the wonderful utility bonnie++ I’ve got a quick question to help me understand something about benchmarking my system. I’ve got a Slice on Slicehost, just a small one with 256MB that I use for some personal projects, and when I run a command like this:


/usr/sbin/bonnie++ -d /tmp/foo -n 256

it runs really quickly. However, when I run it at home on my home PC with 8GB of RAM it takes forever. I suspect it has to do with the “Chunk Size” of Bonnie++, but could anybody explain to me why they are different?

Thanks,

Joe

TheDelChop wrote:
> Having recently discovered the wonderful utility bonnie++ I’ve got a
> quick question to help me understand something about benchmarking my
> system. I’ve got a Slice on Slicehost, just a small one with 256MB that
> I use for some personal projects, and when I run a command like this:
>
>
> Code:
> --------------------
>
> /usr/sbin/bonnie++ -d /tmp/foo -n 256
>
> --------------------
>
>
> it runs really quickly. However, when I run it at home on my home PC
> with 8GB of RAM it takes forever. I suspect it has to do with the
> “Chunk Size” of Bonnie++, but could anybody explain to me why they are
> different?

Bonnie++ will use a size that is TWICE whatever your memory size is to
attempt to avoid memory cache optimizations which might make the storage
device appear to be unrealistically fast.

Ah I see, so its the size of the chunk that effects the run time of bonnie++?