Hard disk driver (HDD) 因為有著低成本低錯誤率的原因，因此在storage market中佔有一席之地。然而，Conventional Magnetic Recording(CMR)在提高areal density的方面因受到superparamagnetic effect的限制，目前已達到瓶頸。最近新型的track layout為Interlaced Magnetic Recording (IMR)，IMR透過交錯重疊track的方式以達到更高的areal density。在IMR中，可以自由的寫入top track，而寫入bottom track時，由於會破壞相鄰top tracks中的資料，需要透過Read-Modify-Write (RMW) process以確保資料的完整性。然而，RMW process不但會增加write amplification以也造成performance overhead，尤其當bottom track中存有hot data時，RMW process所造成的overhead將會更加嚴重。本篇論文提出Track Data Placement Strategy(TDPS)，將較頻繁更新的資料分配至top track，以降低RMW process所造成的overhead。Track Allocator將write request size較小的新資料分配至top tracks，Track Data Migrator在合適的時間點搬移clod track data至bottom tracks，以及搬移hot track data至top tracks。我們在IMR模擬器中實現TDPS以及TrackLace，並使用real world I/O trace以評估TDPS的效能。經實驗表明，與TrackLace相比，TDPS減少write amplification 22.0%，減少write latency 28.0%。

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