"ipig" <[EMAIL PROTECTED]> writes:
>In your example, it seems that process B is the first such waiter( the
> request of B conflicts AccessShareLock).
No. Better go study
http://developer.postgresql.org/docs/postgres/explicit-locking.html#LOCKING-TABLES
After looking at the example again, co
" ;
Sent: Monday, May 29, 2006 11:51 PM
Subject: Re: [HACKERS] some question about deadlock
> "ipig" <[EMAIL PROTECTED]> writes:
>> That is to say, if p0 wants to lock A again, then p0 will be put before
>> p1, and p0 will be at the head of the queue. Why
"ipig" <[EMAIL PROTECTED]> writes:
> That is to say, if p0 wants to lock A again, then p0 will be put before
> p1, and p0 will be at the head of the queue. Why do we need to find the first
> waiter which conflicts p0? I think that p0 must be added at the head of the
> wait queue.
Your analy
head, since
the first waiter in the queue must conflict with the lock-held process.
Best wishes.
- Original Message -
From: "Bruce Momjian"
To: "ipig" <[EMAIL PROTECTED]>
Cc:
Sent: Monday, May 29, 2006 11:26 PM
Subject: Re: [HACKERS] some question about dead
Alvaro Herrera wrote:
> ipig wrote:
> > Hi,
> > Thanks for your reply.
> > I changed the format to plain text.
> >
> > For the question, suppose that process p0 held the lock of object A,
> > and the wait queue for A is p1,p2,p3,, that process p1 is the first
> > waiter in the qu
ipig wrote:
> Hi,
> Thanks for your reply.
> I changed the format to plain text.
>
> For the question, suppose that process p0 held the lock of object A, and
> the wait queue for A is p1,p2,p3,, that process p1 is the first waiter in
> the queue.
> Since p1 is in the wait que
-
From: "Bruce Momjian"
To: "ipig" <[EMAIL PROTECTED]>
Cc:
Sent: Monday, May 29, 2006 9:49 PM
Subject: Re: [HACKERS] some question about deadlock
> ipig wrote:
>> Hi,
>>
>> Below is the notes from postgresql-8.1.3/src/backend/storage/lmgr/README:
>&g
ipig wrote:
> Hi,
>
> Below is the notes from postgresql-8.1.3/src/backend/storage/lmgr/README:
>
>
> Lock acquisition (routines LockAcquire and ProcSleep) follows these rules:
>
> 1. A lock request is granted immediately if it does not conflict with
> any existing or waiting lock request, or i
Hi,
Below is the
notes from postgresql-8.1.3/src/backend/storage/lmgr/README:
Lock acquisition (routines LockAcquire and ProcSleep) follows
these rules:
1. A lock request is granted immediately if it does not
conflict withany existing or waiting lock request, or if the pr
