Re: [PATCH] Avoid reusing the same TCP port number

[Valentin Dornauer]

Hello Andrey,

On Thu, Jul 03, 2014 at 10:41:25PM +0400, Andrey Borzenkov wrote:
> May be you can simply use grub_get_time_ms()? After all, we are not
> interested in exact time, just in some pseudo-random distribution. It
> should have less overhead than grub_get_datetime(). 

I finally got around to trying out your suggestion concerning the
TCP source port "randomization". The main problem I see with using
the TSC's value instead of the current time of day (in seconds)
is that it will have approximately the same value every time the
machine is rebooted and reaches the point where the first file is
loaded. This means that clashes are way more likely than with the
RTC based solution, at least for the first file. Little or no network
jitter could mean even more collisions.

Do you think it's still worth the effort to change the previously
proposed [1] patch?

Thanks
Valentin

[1] http://lists.gnu.org/archive/html/grub-devel/2014-07/msg00000.html