Re: log chunking broken with large queries under load

On 04/02/2012 12:44 PM, Tom Lane wrote:
> Andrew Dunstan<andrew@dunslane.net>  writes:
>> On 04/02/2012 12:00 PM, Tom Lane wrote:
>>> This seems like it isn't actually fixing the problem, only pushing out
>>> the onset of trouble a bit.  Should we not replace the fixed-size array
>>> with a dynamic data structure?
>> But maybe your're right. If we do that and stick with my two-dimensional
>> scheme to keep the number of probes per chunk down, we'd need to reorg
>> the array every time we increased it. That might be a bit messy, but
>> might be ok. Or maybe linearly searching an array of several hundred
>> slots for our pid for every log chunk that comes in would be fast enough.
> You could do something like having a list of pending chunks for each
> value of (pid mod 256).  The length of each such list ought to be plenty
> short under ordinary circumstances.
>
>             


Yeah, ok, that should work. How big would we make each list to start 
with? Still 20, or smaller?

cheers

andrew