gettimeofday() in hping

[Ivan Voras]

On 23/01/2008, Stefan Lambrev <stefan.lambrev at moneybookers.com> wrote:
> Greets,
>
> Now I have final results with Linux and FreeBSD on the same hardware
> CPU: Intel(R) Xeon(R) CPU 3070  @ 2.66GHz - dual core
> Lan: em0 at pci0:3:0:0: class=0x020000 card=0x10bc8086 chip=0x10bc8086
> rev=0x06 hdr=0x00
>     vendor     = 'Intel Corporation'
>     device     = '82571EB Gigabit Ethernet Controller (Copper)'
>     class      = network
>     subclass   = ethernet
>
> FreeBSD releng_7_0 from today - amd64, sched_ule.
>
> ACPI-Fast - 6.187 MB/s
> TSC - 9.455 MB/s
> dummy - 9.577 MB/s
>
> Linux rambo2 2.6.22-14-generic #1 SMP Tue Dec 18 05:28:27 UTC 2007
> x86_64 GNU/Linux - kubuntu
>
> TSC - 19.456 MB/s
> acpi_pm - 15.394 MB/s
> jiffies - 19.480 MB/s
>
> This is really not what I expected.

For once, it's something I expected :) I just hope it isn't one of
those cases where Kris absolutely cannot reproduce it and arrives at
numbers in favour of FreeBSD :)
(just joking here, absolutely no ill feelings involved).

It would be helpful if you post exact command line arguments from all cases.

> The other thing that bothers me is, that under freebsd is quite easy to get:
> [send_ip] sendto: No buffer space available
> It happens almost always on my laptop just few seconds after I start
> hping with timecounter=TSC

I'm not sure, but from what I understood of Robert Watson's
explanation in the big ZFS thread on -current, maybe increasing
kmem_size (exactly as for ZFS...) could help you with these buffers.