Design, Implementation, and Performance Evaluation of Flash ...

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S. J. AHN, J. M. CHOI, D. H. LEE, S. H. NOH, S. L. MIN AND Y. K. CHO
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Ci: application code execution for initialization
Co: applicatio ncode execution for outputting overall result
Cn: application code execution for n-th data unit
D: device driver code execution
S: stub code execution
F: file system code execution
M: media access
T: data transfer
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(a) T comp = 2, phase (1).
(b) T comp = 3, phase (2.a).
(c) Tcomp = 4, phase (2.b).
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(d) Tcomp = 5, phase (3).
Fig. 8. Operation examples of the conventional storage device and FSOC.
used in our experiments is the CompactFlash memory card that we described in the previous
section. This card has exactly the same hardware and software configuration as the
one on which the FSOC prototype was implemented. The relationship between the host
and the storage devices that it operates is shown in Fig. 9. For the host system, we used
an embedded system development board with an ARM920T core running the Linux
2.4.18 operating system. The same host is used for both the FSOC and the conventional
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