The International Arab Journal of Information Technology (IAJIT)


Least Recently Plus Five Least Frequently Replacement Policy (LR+5LF)

  In  this  paper,  we  present  a  new  block  replacement  policy  in  which  we  proposed  a  new  efficient  algorithm  for  combining  two  important  policies  Least  Recently  Use d  (LRU)  and  Least  Frequently  Used  (LFU).  The  implem entation  of  the  proposed policy is simple. It requires limited calc ulations to determine the victim block. We proposed  our models to implement  LRU  and  LFU  policies.  The  new  policy  gives  each  blo ck  in  cache  two weighing  values  corresponding  to  LRU  and  LFU  policies.  Then  a  simple  algorithm  is  used  to  get  th e  overall  value  for  each  block.  A  comprehensive  com parison  is  made  between  our  Policy  and  LRU,  First  In  First  Out  (FIF O),  V-WAY,  and  Combined  LRU  and  LFU  (CRF)  policies.   Experimental  results show that the LR+5LF replacement policy  significantly reduces the number of cache misses. W e modified simple scalar  simulator  version  3  under  Linux  Ubuntu  9.04  and  we  used  speccpu2000  benchmark  to  simulate  this  policy.  The  results  of  simulations  showed,  that  giving  higher  weighing  to  LFU  policy  gives  this  policy  best  performance  chara cteristics  over  other  policies. Substantial improvement on miss rate was  achieved on instruction level 1 cache and at level 2 cache memory. 

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[17] Zhansheng L., Dawei L., and Huijuan B., CRFP: A Novel Adaptive Replacement Policy Combined the LRU and LFU Policies, in Proceedings of IEEE 8 th International Conference on Computer and Information Technology Workshops , Sydney, pp. 72079, 2008. Adwan AbdelFattah is an assistant professor at the Computer Science Department of the Arab American University of Jenin, Palestine. Previously, he worked at Philadelphia and Zarqa Private University. He received his PhD from the National Technical University of Ukraine in 1996. His research interests include computer networks, computer architecture, cryptography, networks security, authentication and digital signa ture. Aiman Abu Samra is an IEEE and computer society member. He received his PhD from the National Technical University of Ukraine in 1996. Currently, he is an assistant professor at the Computer Engineering Department at the Islamic University of Gaza, Palestine. His research interests include computer architecture, computer networks and software engineering. He managed several funded projects in cooperation with industr y. He teaches several courses on computer architecture and computer networks.