Re: [Nbd] performance

[Wouter Verhelst <w@...112...>]

On Wed, Jan 05, 2011 at 06:28:54PM +0100, folkert wrote:
> Hi,
> 
> I have the feeling somthing is not good in my setup as it seems the
> performance looks as if it can be better.
> The setup: quadcore (Q9450) @ 2,1GHz with 8GB ram.
> On the server I run nbd-server and nbd-client via localhost.
> The nbd-server has a sparse file of 10GB in a ramdisk (tmpfs).
> Now when I create an ext2 filesystem (no journal overhead) and run
> iozone I get the following values:
>                                                    random  random    bkwd   record
>      KB  reclen   write rewrite    read    reread    read   write    read  rewrite
> 2097152     256  601977  699077   930964   932460  928055  706410 1011458   814914
> Compare that with iozone directly in the ramdisk:
>                                                    random  random    bkwd   record
>      KB  reclen   write rewrite    read    reread    read   write    read  rewrite
> 2097152     256 1497485 2211397  3293086  3318772 3231160 2267725 3268985 4805781
> 
> Quit a large difference isn't it?

That comparison involves nbd-server running on localhost, I presume?

-- 
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