low outgoing throughput over CSLIP

low outgoing throughput over CSLIP

Post by C. Patrick L » Sat, 05 Mar 1994 01:54:05



I am using dip to connect a Linux box to a ethernet.  The server is also
a Linux box, and both are running 0.99pl15.  Here's the configuration:

               38.4k          38.4k
       Linux A  <---- CSLIP ----> Linux B         Sun C
                     v.32bis        |              |
                                    |              |
                                ----+--- ethernet -+---

I'm able to do telnet from A to C quite well, so I believe I have my
CSLIP set up correctly.  I can also download data from C using ftp, with
throughput of about 1.5k cps (gz files).  When I try to upload to C,
however, the throughput is terrible.  Netstat on A shows that there is
data on Send-Q waiting to go to C, but somehow Linux is not pushing it
through (the modem LED doesn't flash either).  I have similar problem
with X client from C: Send-Q is non-zero on Linux, but if I wait long
enough it is cleared (both Send-Q and Recv-Q on C are clear).

My CSLIP has MTU 1500.  The problem seems to be more severe with
smaller MTU.

Any suggestions?
--
---------------------------------------------------------------
C. Patrick Lai                     Premenos Corporation

(510) 602-2000 x2112               Concord, CA 94520

 
 
 

low outgoing throughput over CSLIP

Post by Charles Hedri » Sun, 06 Mar 1994 05:15:55



Quote:>I am using dip to connect a Linux box to a ethernet.  The server is also
>a Linux box, and both are running 0.99pl15.  Here's the configuration:
>               38.4k          38.4k
>       Linux A  <---- CSLIP ----> Linux B         Sun C
>                     v.32bis        |              |
>                                    |              |
>                                ----+--- ethernet -+---

As I recall, there was a serious bug in pl15 with forwarding onto
CSLIP.  The problem is that the IP forwarding code sometimes passed
the device level too large a byte count.  This may or may not matter
for Ethernet, but was fatal for CSLIP, because CSLIP omits the
datagram length field in the IP header.  It reconstructs the datagram
size from the physical packet size.  The end result was an incorrect
reconstructed IP header, which caused a checksum failures.
Unfortunately I'm hazy about which version this bug was fixed in, but
I think it was pl15a or shortly thereafter.

 
 
 

1. low outgoing throughput over CSLIP


few days ago, asking for help on improving outgoing throughput of TCP
over CSLIP.  Alan Cox responded with e-mail, suggesting that I try
"pl15f or later (preferably pl15j or later)".  I put pl15j on both my
CSLIP server and client, and now I have comparable inbound and outbound
TCP throughput.  Thanks to Alan.


 bounced.  Hope you get your problem resolved too with pl15j.
]
--
---------------------------------------------------------------
C. Patrick Lai                     Premenos Corporation

(510) 602-2036 x2112               Concord, CA 94520

2. Web Vulnerability Scanner

3. UDP throughput tool: unusually low throughput

4. GCC 2.2.2 parse error before (

5. : ftp throughput and socket priority over a CSLIP link?

6. Forgotten root password

7. Maximizing CSLIP throughput

8. PDF documentation ?

9. low slip throughput

10. StorEdge 6320 low throughput. How to tune?

11. Serial Port Throughput Too Low?

12. low throughput via ppp link of linux routers

13. low throughput DDS4 drive