Re: Add GUC to tune glibc's malloc implementation.

Ronan Dunklau <ronan(dot)dunklau(at)aiven(dot)io> writes:
> Le jeudi 22 juin 2023, 15:49:36 CEST Tom Lane a écrit :
>> Aren't these same settings controllable via environment variables?
>> I could see adding some docs suggesting that you set thus-and-such
>> values in the postmaster's startup script. Admittedly, the confusion
>> argument is perhaps still raisable; but we have a similar docs section
>> discussing controlling Linux OOM behavior, and I've not heard much
>> complaints about that.

> Yes they are, but controlling them via an environment variable for the whole
> cluster defeats the point: different backends have different workloads, and
> being able to make sure for example the OLAP user is memory-greedy while the
> OLTP one is as conservative as possible is a worthwile goal.

And what is going to happen when we switch to a thread model?
(I don't personally think that's going to happen, but some other
people do.) If we only document how to adjust this cluster-wide,
then we won't have a problem with that. But I'm not excited about
introducing functionality that is both platform-dependent and
unsupportable in a threaded system.

regards, tom lane