[pptp-server] pptpd 0.9.16 / Win98 performance problem

[Philip Van Baren]

Chris,

When you tweaked the PCKT_RECV_WINDOW_SIZE, what values did you try?  With
my setup, using a value of 1 gives poor performance, 2 through 8 give OK
performance, and above 8 (or matching the other side's value, like is done
in 0.9.16) results in lots of dropped packets.

i.e. try making the following change in ctrlpacket.c to see if this works
better:

/* lets match their window size for now... was htons(PCKT_RECV_WINDOW_SIZE)
 */
out_call_rply.pckt_recv_size = htons(4); /* out_call_rqst->pckt_recv_size;
*/

Philip Van Baren

> -----Original Message-----
> From: pptp-server-admin at lists.schulte.org
> [mailto:pptp-server-admin at lists.schulte.org]On Behalf Of Chris Hyde
> Sent: Friday, September 10, 1999 9:08 PM
> To: pptp-server at lists.schulte.org
> Subject: [pptp-server] pptpd 0.9.16 / Win98 performance problem
>
>
> Hi there,
>
> Has anything been resolved with the pptpd / Windows 98 performance
> issue? I've just read through the archives and there seems to be
> no answer.
>
> My problem:
>
> RedHat 6.0 2.2.10 kernel pptpd 0.9.16 Server on a 3Mb/s fibre
> Win98 client on a cable modem connection.
>
> Usual ping is ~25ms.
>
> Connect via VPN and start a ping on the server back to my client:
>
> PING x.x.x.x (x.x.x.x): 56 data bytes
> 64 bytes from x.x.x.x: icmp_seq=0 ttl=128 time=33.3 ms
> 64 bytes from x.x.x.x: icmp_seq=2 ttl=128 time=32.5 ms
> 64 bytes from x.x.x.x: icmp_seq=3 ttl=128 time=32.9 ms
> 64 bytes from x.x.x.x: icmp_seq=4 ttl=128 time=31.7 ms
> 64 bytes from x.x.x.x: icmp_seq=5 ttl=128 time=35.8 ms
> 64 bytes from x.x.x.x: icmp_seq=6 ttl=128 time=35.6 ms
>
> All great so far, then I actually use the connection from the client
> side (hit an internal website). Before the website is loaded I see:
>
> 64 bytes from x.x.x.x: icmp_seq=10 ttl=128 time=42.2 ms
> 64 bytes from x.x.x.x: icmp_seq=11 ttl=128 time=60.6 ms
> 64 bytes from x.x.x.x: icmp_seq=13 ttl=128 time=2690.4 ms
> 64 bytes from x.x.x.x: icmp_seq=14 ttl=128 time=4331.3 ms
> 64 bytes from x.x.x.x: icmp_seq=18 ttl=128 time=495.5 ms
> 64 bytes from x.x.x.x: icmp_seq=19 ttl=128 time=6763.5 ms
> 64 bytes from x.x.x.x: icmp_seq=20 ttl=128 time=6072.7 ms
> 64 bytes from x.x.x.x: icmp_seq=21 ttl=128 time=7075.6 ms
> 64 bytes from x.x.x.x: icmp_seq=22 ttl=128 time=6081.9 ms
> 64 bytes from x.x.x.x: icmp_seq=23 ttl=128 time=6036.2 ms
> 64 bytes from x.x.x.x: icmp_seq=24 ttl=128 time=5977.3 ms
> 64 bytes from x.x.x.x: icmp_seq=25 ttl=128 time=10531.3 ms
>
> ... and then the connection will finally break down entirely and no
> data will be transferred. There is not a connection problem between me
> and the server at all. At the time of testing I was getting <20ms and
> no packet loss.
>
> I tried tweaking the PCKT_RECV_WINDOW_SIZE and this improved performance
> but I would eventually get the same out-of-sync like behaviour where
> the pings would go through the roof and stay there.
>
> Higher WINDOW_SIZE's would just put this off for a few more pages ...
>
> Anyone have any answers for this one?
>
>
> --
> **********************************************************************
> Chris Hyde
> The Electric Mail Company
>
> Voice : (604) 482-1111                  Info  :   www.electricmail.com
> Fax   : (604) 482-1110                  Email : chris at electricmail.com
>
> Lister:  We want no muffins, no toast, no tea cakes, no buns, baps,
>          baggets or bagels. No croissants, no crumpets, no pancakes,
>          no potato cakes, and no hot cross buns. And definitely no
>          smegging flapjacks!
> Toaster: Ah! So you're a waffle man!
>
> ***********************************************************************
>
> _______________________________________________
> pptp-server maillist  -  pptp-server at lists.schulte.org
> http://lists.schulte.org/mailman/listinfo/pptp-server
> List services provided by www.schulte.org!
>