G'day Frank.
> -----Original Message-----
> From: Frank Ch. Eigler [mailto:fche@xxxxxxxxxx]
> Sent: Saturday, 3 October 2015 7:20 AM
> To: Ken McDonell <kenj@xxxxxxxxxxxxxxxx>
> Cc: 'Martins Innus' <minnus@xxxxxxxxxxx>; 'pcp developers'
> <pcp@xxxxxxxxxxx>
> Subject: Re: [pcp] pmcd restart race condition
>
> ...
> That backgrounding was probably done to hide the latency of first-time
> pmcd startup doing all the pmda Installs.
But if we need PMDAs X, Y and Z auto installed, is there really any point in
getting pmcd started before X, Y and Z are actually installed? I can't
think of any bad side-effect of pmcd taking longer to start first-time.
> ...
> Yes, as long as that is preserved throughout the process, sounds good.
> ... and then actually:
>
> - _pmda_setup &
> + PMDA_SETUP_RUNNING=yes _pmda_setup
>
> might not even need to take away the "&", as the environment variable
> should preclude reentrancy to this part.
Fair point, but I am a little concerned that there may be some other race
condition in the rc script _after_ the pmda_setup call and not running in
the background means we won't expose this risk more than we need to.
Probably needs a review of this to see if there is more than a nested
pmda_setup that needs to be guarded by $PMDA_SETUP_RUNNING ... I'll wait for
Martins feedback and until I can discuss with Nathan before committing
anything.
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