US Patent 7877424 Quota enforcement with transacted file systems

Aspects of the subject matter described herein relate enforcing quotas in transactional file systems. In aspects, a filter monitors operations that may affect quota usage/charge of a file system object having a quota allotment. In doing so, the filter determines a quota value outside of any transaction for the object and a quota value associated with at least one transaction affecting the object. The filter receives a request that involves the use of additional quota. The filter then determines whether to allow or fail the request depending on whether enough quota is available to satisfy the request.