Resolving a page fault requires loading the needed page into…

Resolving a page fault requires loading the needed page into memory from disk. This disk read operation dominates the time needed to resolve the page fault. The page read in from disk is placed in a frame; processes are given a set allocation of frames to use while they run. Why does resolving this page fault take twice as long if no ‘clean’ pages are found in the frames available to this process?

L.M. 46 year old male. Presents to your office today with co…

L.M. 46 year old male. Presents to your office today with complaints of swollen left leg that started after his international travel. His PMH includes controlled HTN.  On exam his HR was 102 and rest of vitals were normal with no shortness of breath.  His calculated Well’s Criteria for PE was moderate risk.    Which of the follow up testing is the most appropriate in this setting?