HSH_Private & expire superseded

[Poul-Henning Kamp]

In message <5233A227.9070609 at schokola.de>, Nils Goroll writes:
>On 09/13/13 09:43 AM, Poul-Henning Kamp wrote:

>For the time being: This does not change the fact that the exp thread will still 
>need to lock the objhead list, right?

In the case were somebody else nukes an object (de-dup, length
restriction) the objcore is taken off the objhdr list by that
thread and delivered to EXP on its "inbox" list, so no further
objhdr locking will be required.

The trick is that the objcore can hang out on the exp-inbox list
until its refcount becomes zero.

For LRU and obj.keep expiry, there's no way around locking objhead
if we want to recover the storage in a timely way.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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