Re: lazy vxid locks, v3 - Mailing list pgsql-hackers

From Jeff Davis
Subject Re: lazy vxid locks, v3
Date
Msg-id 1312212079.29391.111.camel@jdavis
Whole thread Raw
In response to Re: lazy vxid locks, v3  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: lazy vxid locks, v3
List pgsql-hackers
On Mon, 2011-08-01 at 08:12 -0400, Robert Haas wrote:
> > Is the "&& LocalTransactionIdIsValid(lxid)" a guard against calling
> > VirtualXactLockTableCleanup twice? Can that happen? Or is it just
> > defensive coding to avoid making an additional assumption?
> 
> lxid there is just a local variable storing the value that we
> extracted from fpLocalTransactionId while holding the lock.  I named
> it that way just as a mnemonic for the type of value that it was, not
> intending to imply that it was copied from MyProc->lxid.

I know, this is the other purpose of fpLocalTransactionId that I was
talking about. Is it just a guard against calling
VirtualXactLockTableCleanup twice?

Regards,Jeff Davis



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