the RSP8 has 8 megs of MEMD (unlike the RSP1/2/4/4+ which have 2 megs).
this is what you are seeing. to see the packet memory on a VIP, you
will need to do a "show diag" or you can do a
"show controller vip X show-tech" or if-con into the vip and do a
"show mem summ" (please note that we discourage doing the latter).
the VIP is a particle based platform, so the packet memory will get divied up
into particles and assigned to interfaces. some of it will be held in
reserve for QoS, public (fallback) pools, and for other things.
there are no changes (afaik) in the way the VIP4 talks to the CyBus.
but the VIP4 PCI bw is 800 mbps (unlike the VIP2 which is 400 mbps)
cheers
.siva
>
> Eric,
>
> This is what is confusing. I am looking in my RSP8 and I see 8MB MEMD:
>
> sh contr cbus
> MEMD at 40000000, 8388608 bytes (unused 13184, recarves 2, lost 0)
> RawQ 48000100, ReturnQ 48000108, EventQ 48000110
> BufhdrQ 48000148 (1147 items), LovltrQ 48000160 (36 items, 2016 bytes)
> IpcbufQ 48000170 (40 items, 4096 bytes)
> IpcbufQ_classic 48000168 (16 items, 4096 bytes)
> 3570 buffer headers (48002000 - 4800FF10)
> pool0: 11 buffers, 256 bytes, queue 48000150
> pool1: 942 buffers, 1536 bytes, queue 48000158
> pool2: 1374 buffers, 4544 bytes, queue 48000178
> pool3: 4 buffers, 4576 bytes, queue 48000180
>
> But the docs say the the RSP8 ships w/64MB packet memory. The RSP4 has 2MB
> SRAM (packet memory).
>
> What happened to the other 56MB SRAM? I think this may be a misprint - 64
> MB is the default DRAM option. I checked the RSP8 datasheet and it is
> explicit in stating that there is 8MB SRAM. Maybe I'm crazy.
>
> On the VIP4 thing, can you explain what changes are made to increase the
> bandwidth? I recall hearing something about expanding the CyBUS to 64 bits
> by using the 2 16bit channels and the the 32 bit channel used by the
> VIP2-50. Is this correct? I also am aware of the PCI enhancements to
> increase throughput to 800 Mbps (I assume 400/PA). There isn't much in the
> docs on this, and if need be I can get it from the account team, but I
> figured you may have something fast off the top of your head... ;-)
>
> thanks,
> chris
>
>
> > 8MB of MEMD on RSP8, not 64MB. But it's still a lot more than 2MB.
> >
> > >
> > > Does RSP8 add 'bandwidth' to the CyBUS or do we need
> > VIP4-80s to get 4Gbps
> > > (I seem to remember something about a CzBUS)? I want to
> > see how far the
> > > 7513 can go.
> > >
> >
> > You need the VIP4s (50 or 80) to get more bandwidth.
> >
> > > Anyway, the important point to remember is that true
> > distributed switching
> > > on the RSP platforms only occurs between PA's in the same
> > VIP (unlike the
> > > GSR). InterVIP switching requires the RSP to manage access
> > to MEMD between
> > > VIPs (hence the high amount of RSB drops when the load is high).
> > >
> >
> > Intra-vip switching isn't always purely local to the VIP. There are
> > some timing and starvation issues where with some PAs, we still send
> > traffic to MEMD. It's not often, and it only shows up in the
> > high-speed PAs, and I'm not sure if VIP4s alleviate that at all, but
> > that's how a few PAs on VIP2s behave.
> >
> >
> >
> > eric
> >
>
This archive was generated by hypermail 2b29 : Sun Aug 04 2002 - 04:12:39 EDT