Robb, Would it be possible to insert a call to msync (perhaps with MS_ASYNC set) after each queue entry modification so that writes are scheduled as changes are made? I'd be happy to experiment, but I wasn't sure where such a call should be inserted in the code. I noticed msync is called in pq.c if USE_MSYNC is defined but that appears to only be called when closing out the queue. Defining it had no useful effect. -------------------------------------------------------- David Wojtowicz, Research Programmer/Systems Manager Department of Atmospheric Sciences Computer Services University of Illinois at Urbana-Champaign email: address@hidden phone: (217)333-8390 --------------------------------------------------------