Neil Conway wrote:
> Magnus Hagander wrote:
>> Anyway. Attached patch adds this to the bgwriter shared memory. Is it
>> safe to do this, and then just have a regular function running in a
>> normal backend pulling out the value and returning it to the user,
>> without locking?
> If the variable is an int64, I don't believe so: the architecture might
> not implement atomic read/writes of int64 values.
Advertising
Ok. But it should be safe if it's int32?
Actually, since it's just statistics data, it wouldn't be a problem that
it's not atomic, I think. If we really unlucky, we'll get the wrong
value once. But most systems that poll such statistics can deal with
that, in my experience.
Then again, a normal int shouldn't be a problem either.
//Magnus
---------------------------(end of broadcast)---------------------------
TIP 9: In versions below 8.0, the planner will ignore your desire to
choose an index scan if your joining column's datatypes do not
match
