Using 2013 SP1, publishing to Broker DB and file system.
Whenever a specific component is published, it stays in "Committing Deployment" phase and never succeeds in the publishing queue. Even after few tries, the issue continues. After few number of tries, deployer doesn't handle any more item and we see "Throttled" status in the queue. It then requires deployer restart. This component is not placed on any page and has got only one component presentation. Custom metadata is included in the component presentation output. 3 images are impilcitely published with this component.
As wecan see in the deployer logfile, this specific transaction doesn't have any record after logging "Precommit" phase. Last info that we see is "PreCommitPhase - Executing workers for transaction: tcm:0-11272601-66560 with 19 Workers". For successfully published items, we see more records in the deployer log after this step. We are wondering whether the deployer never comes out of handling this item and when the same item is published few times, all threads are into the same issue which then causes the deployer to say "Throttled".
Interestingly the same version of the component was earlier published successfully.
What is the root cause of this issue and how can it be fixed?