Re: Multiple Concurrent Updates of Shared Resource Counter

Le jeudi 7 juin 2012 09:53:48, Nir Zilberman a écrit :
> Hi.
>
> We are handling multiple concurrent clients connecting to our system -
> trying to get a license seat (each license has an initial capacity of
> seats). We have a table which keeps count of the acquired seats for each
> license. When a client tries to acquire a seat we first make sure that the
> number of acquired seats is less than the license capacity. We then
> increase the number of acquired seats by 1.
>
> Our main problem here is with the acquired seats table.
> It is actually a shared resource which needs to be updated concurrently by
> multiple transactions.
>
> When multiple transactions are running concurrently - each transaction
> takes a long time to complete because it waits on the lock for the shared
> resource table.
>
> Any suggestions for better implementation/design of this feature would be
> much appreciated.

maybe you can manage something around UNIQUE (license_id,license_seat_number).

It depends of what you achieve, and the tables structures you have.
--
Cédric Villemain +33 (0)6 20 30 22 52
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