Abstract: Managing locks under conditions wherein there is a first shared hold on a lock. There is a first pending request for a first exclusive hold on the lock; the first pending request for said first exclusive hold is made after the first shared hold was granted. There is a second pending request for a second exclusive hold on the lock; the second pending request for the second exclusive hold is made after the first pending request for the first exclusive hold. There is a third pending request for a second shared hold; the third pending request for the second shared hold is made after the second pending request for the second exclusive hold. First program instructions grant one of the pending requests for an exclusive hold in response to the first shared hold being released. Second program instructions grant the third pending request for the second shared hold in response to release of the exclusive hold previously granted in response to the one request for an exclusive hold.

Abstract: Managing locks under conditions wherein there is a first shared hold on a lock. There is a first pending request for a first exclusive hold on the lock; the first pending request for said first exclusive hold is made after the first shared hold was granted. There is a second pending request for a second exclusive hold on the lock; the second pending request for the second exclusive hold is made after the first pending request for the first exclusive hold. There is a third pending request for a second shared hold; the third pending request for the second shared hold is made after the second pending request for the second exclusive hold. First program instructions grant one of the pending requests for an exclusive hold in response to the first shared hold being released. Second program instructions grant the third pending request for the second shared hold in response to release of the exclusive hold previously granted in response to the one request for an exclusive hold.