Re^2: Multiple write locking for BerkeleyDB

http://qs321.pair.com?node_id=682463

in reply to Re: Multiple write locking for BerkeleyDB
in thread Multiple write locking for BerkeleyDB

Thanks for the url. Wrt BerkeleyDB I was unable to find any Read Modify Write locking code. It looks like CDS was used in an automatic fashion. I'm guessing I need to invoke lock_vec and its friends but I'm not sure how.

Comment on Re^2: Multiple write locking for BerkeleyDB

Replies are listed 'Best First'.
Re^3: Multiple write locking for BerkeleyDB by perrin (Chancellor) on Apr 23, 2008 at 19:16 UTC
No, that's just it: BDB handles the locking for you. You don't need to do any explicit locking.	[reply]
Re^4: Multiple write locking for BerkeleyDB by dino (Sexton) on Apr 23, 2008 at 19:32 UTC
I thought that with an update I need to wrap the read and the write in an overall lock. Doesn't the built in automatic locking, lock the operations separately?	[reply]
Re^5: Multiple write locking for BerkeleyDB by perrin (Chancellor) on Apr 23, 2008 at 20:00 UTC
You're saying you want to get an exclusive lock before you start your read and hold it until you finish the update? That will require some lower level access. BerkeleyDB can do it, but I think you'll have to use the more complex approach and run a deadlock daemon, and I don't have sample code for it. This is trivial with MySQL, so it might be easier to give that another try.	[reply]

In Section Seekers of Perl Wisdom