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Conference netcad::hub_mgnt

Title:DEChub/HUBwatch/PROBEwatch CONFERENCE
Notice:Firmware -2, Doc -3, Power -4, HW kits -5, firm load -6&7
Moderator:NETCAD::COLELLADT
Created:Wed Nov 13 1991
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:4455
Total number of notes:16761

1515.0. "DECswitch EF buffer" by SNOFS1::BELLMIKE (Michael Bell) Tue Oct 04 1994 04:55

I have a RFT requiring the Buffer size per port for a DECswitch 900EF. 
I do not seem to be able to find this anywhere, if anyone has seen this 
info I would appreciate a pointer.
Regards
Mike


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1515.1I think this is what you're after....NETCAD::BATTERSBYTue Oct 04 1994 12:275
    I think there are 128 entries for both transmit and receive queues
    for ports 2-7, and 256 entries each for transmit, receive, and mgmt
    queues for port 1.
    
    Bob
1515.2buffer size (bytes)TKOV51::SATO_TETCogito Ergo SumWed Jun 07 1995 05:548
How many buffer size (bytes) do DECswich 900EF and PEswitch 900TX have ?

There are 128 enries for each port 2-7 and 256 entries for port 1 ?

That is ,the buffer size is  128*1.5k bytes,right ?  and 256*4.5k byte,right ?
 
tetsuya

1515.3RE: Buffer size queues....NETCAD::BATTERSBYWed Jun 07 1995 13:127
    Yes, you can think of it in terms of max frame size for both Ethernet 
    and FDDI. Keep in mind that there are 128 entries for both transmit
    *and* receive for each of the 6 Ethernet ports. Also with FDDI, there
    are 256 entries for both transmit and receive, and 256 more entries for
    management queues on FDDI.
    
    Bob
1515.4NETCAD::ANILWed Jun 21 1995 16:1316
    256 buffers of 2 KBytes for each Ethernet port, divided equally between
    receive and transmit.  512 2 KByte buffers for the FDDI port, divided
    equally between receive and transmit plus an additional 1 MB of
    buffering space which is "flexible" buffer size (ie, buffers are
    allocated as per the needs of the incoming packet).  Since Ethernet
    max size is 1518 bytes, each buffer is capable of holding a full-size
    packet.  Since FDDI packets can be up to 4500 bytes long, they are
    chained in successive buffers if necessary.  Another good way of
    looking at it is that we have 0.5 MB of buffer space dedicated to
    each Ethernet port and 2 MB dedicated to the FDDI.
    
    Not that any of this really means much to the typical customer.. what
    they need to know is our performance in congested situations.  The
    Lippis report may be of help, we performed very well.
    
    Anil