Re: tcp_tw_recycle broken?

From: Karl Pickett
Date: Sat Nov 15 2008 - 10:47:27 EST


On Sat, Nov 15, 2008 at 8:09 AM, Andi Kleen <andi@xxxxxxxxxxxxxx> wrote:
> "Karl Pickett" <karl.pickett@xxxxxxxxx> writes:
>>
>> May I just confirm.. is tcp_tw_reuse NOT dependent on receiving timestamps?
>
> The big problem is that both are incompatible with NAT. So if you
> ever talk to any NATed clients don't use it.
>
> -Andi
>
> --
> ak@xxxxxxxxxxxxxxx
>


Hmph. Running the test again - after getting a little sleep -
timestamps do indeed determine if tw_reuse/recyle work. I must not
have let all the tw buckets expire before changing my timestamp
settings last night.

Since
A. I don't want to rely on arbitrary web servers having timestamps
B. People say it breaks NAT for clients, and the settings are global only,

I will just set TCP_TIMEWAIT_LEN to 10 seconds and call it a day.
Sure would be nice if it was a tunable, so only the most heavily
loaded customers could set it...

--
Karl Pickett
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