Re: Statistics Import and Export

On Thu, Feb 29, 2024 at 10:55:20PM -0500, Corey Huinker wrote:
>> That’s certainly a fair point and my initial reaction (which could
>> certainly be wrong) is that it’s unlikely to be an issue- but also, if you
>> feel you could make it work with an array and passing all the attribute
>> info in with one call, which I suspect would be possible but just a bit
>> more complex to build, then sure, go for it. If it ends up being overly
>> unwieldy then perhaps the per-attribute call would be better and we could
>> perhaps acquire the lock before the function calls..? Doing a check to see
>> if we have already locked it would be cheaper than trying to acquire a new
>> lock, I’m fairly sure.
>
> Well the do_analyze() code was already ok with acquiring the lock once for
> non-inherited stats and again for inherited stats, so the locks were
> already not the end of the world. However, that's at most a 2x of the
> locking required, and this would natts * x, quite a bit more. Having the
> procedures check for a pre-existing lock seems like a good compromise.

I think this is a reasonable starting point. If the benchmarks show that
the locking is a problem, we can reevaluate, but otherwise IMHO we should
try to keep it as simple/flexible as possible.

--
Nathan Bossart
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