scheduling off the waiting list
slink at schokola.de
Wed Dec 9 21:13:02 CET 2009
thank you for taking the time to respond.
> What happens here is that another client/thread holds this object
> "busy" while it is being fetched from the backend. Once the object
> is marked unbusy, the waiting threads are relased, and calls hash
My understanding is that the waiting sessions are re-scheduled on threads, right?
> I'm not quite sure you you keep hitting it so many times, it smells
> like som weird situation where the object takes a long time to fetch,
> has no cacheability, but does not get marked "pass" in vcl_fetch ?
I am seeing hsh_rush getting called much more often than I thought it should be
and I don't yet understand why.
What I would really like to see is that the waitinglist gets rescheduled when
the busy object is actually becomes in the cache. I am suspecting this has to do
with calling HSH_Deref(&Parent) in HSH_Unbusy and/or the fact that HSH_Drop
calls both Unbusy and Deref, but I don't understand this yet.
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