Query about HSH_EXPBUSY & HSH_EXP in HSH_Lookup

[Dridi Boukelmoune]

On Thu, Feb 1, 2018 at 9:46 PM, Arvind Narayanan <arvind at cs.umn.edu> wrote:
<snip>
> If busy, is the variable busy_found set to 0 or 1? For expired objects, it
> looks like if it is not busy, then you set the return value to HSH_EXPBUSY,
> shouldn't it be HSH_EXP? Can anyone help me understand this piece of code?
> Because below, the code returns HSH_MISS

It's a bit embarrassing because I've stared hard at this code a couple
months ago, and don't remember the details. I think that HSH_EXPBUSY
means that the object you found during the lookup was expired but
there is an ongoing transaction also matching (hash and variants) your
lookup. So I think in that case your hit is actually a graced object.

But I only tried to remember from the snippet you posted, I didn't
look at the full picture.

Dridi