Re: Shortcoming in CLOBBER_FREED_MEMORY coverage: disk buffer pointers

Jim Nasby <Jim.Nasby@bluetreble.com> writes:
> On 1/24/15 3:31 PM, Tom Lane wrote:
>> Another idea is to teach Valgrind that whenever a backend reduces its
>> pin count on a shared buffer to zero, that buffer should become undefined
>> memory.

> <paranoia>

> Shouldn't this technically tie in with ResourceOwners?

No.  ResourceOwner is just a mechanism to ensure that we remember to call
UnpinBuffer, it has no impact on what the semantics of the pin count are.
The *instant* the pin count goes to zero, another backend is entitled to
recycle that buffer for some other purpose.
        regards, tom lane