Re: Clusterwide pids

["Albert D. Cahalan" <acahalan@cs.uml.edu>]

Lars Marowsky-Bree writes:
>    "Albert D. Cahalan" <acahalan@cs.uml.edu> said:

>> How about this: when a node boots, pass it a PID range.
>
> This leaves us with the chicken and egg problem - how do you
> boot a node which is - at the time of boot - unable to contact
> the cluster?

You don't. It is a mistake to design for this perversion.
Do you, or do you not want a shared PID space? Make up your
mind about this. You don't run an SMP system as multiple
uniprocessor systems, then suddenly decide that you want SMP!

> IMHO, a node should be able to have "local" processes (node id
> part of the CPID = 0). Only after it joined the cluster once
> (and thus was assigned a node id) should processes which need
> a valid CPID be started.

Now what am I supposed to do with the "ps" program I wrote?
Invisible processes? Nope, not at all OK. This is crap too:

  PID TTY          TIME CMD
    1 ?        00:00:03 init
    1 ?        00:00:03 init
    1 ?        00:00:03 init
    1 ?        00:00:03 init
    2 ?        00:00:00 keventd
    2 ?        00:00:00 keventd
    2 ?        00:00:00 keventd
    2 ?        00:00:00 keventd
    3 ?        00:00:10 kswapd
    3 ?        00:00:10 kswapd
    3 ?        00:00:10 kswapd
    3 ?        00:00:10 kswapd
    4 ?        00:00:00 kreclaimd
    4 ?        00:00:00 kreclaimd
    4 ?        00:00:00 kreclaimd
    4 ?        00:00:00 kreclaimd
    5 ?        00:00:00 bdflush
    5 ?        00:00:00 bdflush
    5 ?        00:00:00 bdflush
    5 ?        00:00:00 bdflush
    6 ?        00:00:00 kupdated
    6 ?        00:00:00 kupdated
    6 ?        00:00:00 kupdated
    6 ?        00:00:00 kupdated
    7 ?        00:00:00 mdrecoveryd
    7 ?        00:00:00 mdrecoveryd
    7 ?        00:00:00 mdrecoveryd
    7 ?        00:00:00 mdrecoveryd
31331 pts/0    00:00:00 bash
 9786 tty2     00:00:00 bash
24247 tty2     00:00:00 less
26657 pts/0    00:00:00 ps

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