| Title: | FDDI - The Next Generation |
| Moderator: | NETCAD::STEFANI |
| Created: | Thu Apr 27 1989 |
| Last Modified: | Thu Jun 05 1997 |
| Last Successful Update: | Fri Jun 06 1997 |
| Number of topics: | 2259 |
| Total number of notes: | 8590 |
Hi.
My customer has the following configuration.
DIGITAL UNIX 3.2 as a Polycenter networkes server connected on the FDDI ring
(DEFTA) , On the same ring there is a HP intel PC whith a DEFEA adapter.
I have also tested this configuration inhouse and it gives me the same results.
The throughput on FDDI - FDDI whith DECnsr is ~20-30 Kb/sec
FDDI - Ethernet whith DECnsr is ~250-350 Kb/sec
FDDI - FDDI whith FTP copy is 613.94 Kb/sec
FDDI - Ethernet whith FTP copy is ~500 Kb/sec
It don't matter if i put the PC on Ethernet or the DIGITAL UNIX on Ethernet the
preformance still is the same (~250-350 Kb/sec).
I have traced but i'm not that capable to analyze them.
The location of the traces is --->
KURTAN>>dire SWETSC::usr:<albinsson.fddi>
Directory SWETSC::USR:[ALBINSSON.FDDI]
FTP-FDDI-FDDI_SUM.TXT;1 986 26-JUN-1995 17:38:09.00
FTP-FDDI-FDDI_SUM_DET.TXT;1 817 26-JUN-1995 19:16:29.00
NSR_FDDI-FDDI_SUM.TXT;1 100 26-JUN-1995 14:44:40.00
NSR_FDDI-FDDI_SUM_DET.TXT;1 723 26-JUN-1995 14:38:15.00
Where the NSR* is trace on FDDI runnig DECnsr backup from a NT-server.
And the FTP* is doing a PUT command on the same NT-server.
Any help would be appreciated
/Lars Albinsson
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 1726.1 | MTU on Digital UNIX set to 1500 increases speed. | SWETSC::ALBINSSON | Tue Jun 27 1995 05:25 | 10 | |
Additional information that i got from the customer. If he changes the MTU size on the Digital UNIX system to 1500 the NT-server pushes data of a rate up to ~600 Kb/sec. Can this be Legato Networker client application problem ? Help. /Lars Albinsson | |||||
| 1726.2 | NETCAD::STEFANI | Welcome to the Revolution! | Tue Jun 27 1995 08:52 | 16 | |
>> -< MTU on Digital UNIX set to 1500 increases speed. >-
That's weird. I expect the default MTU on Digital UNIX to be about
4478 bytes since the protocol stacks support native FDDI adapters.
Lowering it shouldn't increase performance across an FDDI-FDDI
connection, but rather, it should create the opposite effect.
>>Can this be Legato Networker client application problem ?
That's possible. I would get a LAN Sniffer trace on the network and
see what packet sizes are getting sent in each of the test
configurations. Also, see if there are retries occurring from either
node that could indicate a protocol compatibility problem or some other
trouble.
/l
| |||||
| 1726.3 | SWETSC::ALBINSSON | Wed Jun 28 1995 05:53 | 3 | ||
The traces location is SWETSC::USR:[ALBINSSON.FDDI]*.* /Lars | |||||
| 1726.4 | Patch available from the NSR folks @ ZSO | 61280::kimpton | Stark Raving Sane | Sat Aug 05 1995 00:19 | 6 |
This is a known problem with the Networker Client for Windows NT and FDDI adapters. There is a note on the subject in DECWET::DECNSR (sorry I forget the details 8-(, and also a patch is now available from them (for both Alpha NT and Intel NT) - contact DECWET::NSR-SUPPORT for details. Andrew 8-) | |||||