新型的分區命名空間 (Zoned Namespace，ZNS) 固態硬碟 (Solid-State Drive，SSD) 解決了傳統 SSD 因隨機寫入造成 SSD 壽命降低的問題，然而其分區循序寫入限制與主機端分區管理的特色，目前還缺少能完整支援 ZNS SSD 的追蹤工具。本論文提出的 TraceIO 為以 Storage Performance Development Kit (SPDK)作為基礎的追蹤工具，可監測與分析應用程式對於 NVMe 儲存系統 (如傳統 SSD 和 ZNS SSD) 的 I/O 行為，並針對 ZNS SSD 能在主機端管理分區的特色，分析應用程式對區塊和分區的讀寫次數，透過 TraceIO 可在未來對管理資料與分區機制時做更適當的安排。此外 TraceIO具備追蹤重放的功能，其中將寫入操作由 Write 命令改為適合 ZNS SSD 使用的 Zone Append 命令，並支援分區管理，使追蹤重放時能重現應用程式管理分區資源的操作。

The novel storage device, Zoned Namespace Solid-State Drive (ZNS SSD), addresses the issue of reduced SSD lifespan due to random writes encountered in traditional SSDs. However, despite its advantages, the ZNS SSD comes with limitations in sequential writes and zones management from the host, and currently lacks comprehensive tracing tools to fully support its functionalities. This research presents TraceIO, a tracing tool built on the basis of SPDK (Storage Performance Development Kit), enabling the monitoring and analysis of application I/O operations on NVMe storage systems, including traditional SSDs and ZNS SSDs. Furthermore, TraceIO analyzes application read and write operations on both blocks and zones, taking into consideration the distinctive feature of ZNS SSD's zone management on the host. This allows for the development of more appropriate data and zone management strategies in the future. Additionally, TraceIO facilitates tracing replay by converting Write commands into Zone Append commands optimized for ZNS SSD utilization while offering zone management support, thus enabling the reproduction of application-managed zone resources during trace replay.

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