DSACK

[Michael Tuexen]

> On 23. Feb 2019, at 11:28, Scheffenegger, Richard <Richard.Scheffenegger at netapp.com> wrote:
> 
> 
> Bin grad am flughafen und hab leider nur HEAD bei mir (und ein iso von 10, wo ich grad versuch, das mit scapy zu checken).
> 
> Falls du schnell einen packetdrill gegen BSD11 ohne D18960 machen kannst, und es da noch DSACKs raussendet, wäre das toll!
> 
> Ich fürchte aber, das das schon längere Zeit kaputt ist - da wir nun doch noch nicht D18960 drinnen haben, wie ich irrtümlich dachte.
OK. I'll take a look.

Have a save trip!

Best regards
Michael
> 
> 
> 
> -----Original Message-----
> From: Michael Tuexen <tuexen at freebsd.org> 
> Sent: Samstag, 23. Februar 2019 11:25
> To: Scheffenegger, Richard <Richard.Scheffenegger at netapp.com>
> Cc: freebsd-transport at freebsd.org
> Subject: Re: DSACK
> 
> NetApp Security WARNING: This is an external email. Do not click links or open attachments unless you recognize the sender and know the content is safe.
> 
> 
> 
> 
>> On 23. Feb 2019, at 10:29, Scheffenegger, Richard <Richard.Scheffenegger at netapp.com> wrote:
>> 
>> Hi,
>> 
>> A colleague pointed me to the stack (HEAD) no longer emitting DSACK options a few days ago...
>> 
>> I was under the impression, that older versions of FreeBSD would send out DSACKs for spurious duplicate packets.
>> 
>> But when I try this script against HEAD, regular cumulative ACKs without DSACK blocks are showing up.
>> 
>> Currently bandwidth starved - but was that a conscious decision? Or was me observing DSACKs never a thing?
> I would say if it is working in stable/11, but not in stable/12 and head, it is a regression.
> 
> Best regards
> Michael
>> 
>> Thanks a lot,
>>  Richard
>> 
>