[Dovecot] performance?/connectivity? issues after server upgrade

[Ed W]

Udo Rader wrote:
> On Fri, 2007-10-19 at 08:46 +0100, Ed W wrote:
>   
>>> I've verified this with various customers and thus I am completely lost
>>> here. The only service affected with this massive slowdown seems to be
>>> dovecot but unfortunately I cannot think of a way to debug the issue ...
>>>   
>>>       
>> Duplex mismatch on the network card?
>>     
>
> grrrrrrrrrrrrrr, yes!!! Checking the link status of the NIC it showed
> that indeed duplexing was giving wrong results. Forcing it into the
> correct mode did not change anything, but finally replacing the card
> with a new one solved the riddle!
>   

Really slow mysterious speeds are nearly always due to massive packet 
loss and 9/10 times this is a duplex mismatch or failing network card.  
Curious huh...

Ed W