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Analysis of flash memory wear based on cache configuration and available memory

Andersson, Markus LU and Hermansson, Filip LU (2023) EITM01 20231
Department of Electrical and Information Technology
Abstract
This thesis aimed at examining the effects of file and disk cache for certain writing patterns and file sizes for Beijer Electronic's human machine interface (HMI) panels with the focus on write amplification factor (WAF). The goal was to determine optimal configurations to reduce WAF for different use cases to prolong the lifetime of Beijer Electronic's HMI panels. A test application and logs were created to measure commands sent over the bus for chosen tests.

It was found that write amplification decreased naturally as file sizes grew. It was also found that enabling disk cache without file cache had the most negative impact on the write amplification factor, but that enabling file cache together with disk cache reduced the negative... (More)
This thesis aimed at examining the effects of file and disk cache for certain writing patterns and file sizes for Beijer Electronic's human machine interface (HMI) panels with the focus on write amplification factor (WAF). The goal was to determine optimal configurations to reduce WAF for different use cases to prolong the lifetime of Beijer Electronic's HMI panels. A test application and logs were created to measure commands sent over the bus for chosen tests.

It was found that write amplification decreased naturally as file sizes grew. It was also found that enabling disk cache without file cache had the most negative impact on the write amplification factor, but that enabling file cache together with disk cache reduced the negative effect as well as improved writing speed. Furthermore, only enabling file cache or not enabling any form of cache resulted in the lowest write amplification factor for file sizes between 10 and 10000 KB, however always resulting in slower execution times than configurations with both caches enabled. It was also found that operating the panels at close to max capacity reduced writing speed because of the internal wear-leveling required for the SD cards during tests to not wear out prematurely, but no increase in write amplification factor was measured. (Less)
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author
Andersson, Markus LU and Hermansson, Filip LU
supervisor
organization
course
EITM01 20231
year
type
H2 - Master's Degree (Two Years)
subject
keywords
flash memory, file cache, disk cache, write amplification factor, over-provisioning, HMI panel, wear leveling
report number
LU/LTH-EIT 2023-951
language
English
id
9133321
date added to LUP
2023-09-19 14:28:10
date last changed
2023-09-19 14:28:10
@misc{9133321,
  abstract     = {{This thesis aimed at examining the effects of file and disk cache for certain writing patterns and file sizes for Beijer Electronic's human machine interface (HMI) panels with the focus on write amplification factor (WAF). The goal was to determine optimal configurations to reduce WAF for different use cases to prolong the lifetime of Beijer Electronic's HMI panels. A test application and logs were created to measure commands sent over the bus for chosen tests. 

It was found that write amplification decreased naturally as file sizes grew. It was also found that enabling disk cache without file cache had the most negative impact on the write amplification factor, but that enabling file cache together with disk cache reduced the negative effect as well as improved writing speed. Furthermore, only enabling file cache or not enabling any form of cache resulted in the lowest write amplification factor for file sizes between 10 and 10000 KB, however always resulting in slower execution times than configurations with both caches enabled. It was also found that operating the panels at close to max capacity reduced writing speed because of the internal wear-leveling required for the SD cards during tests to not wear out prematurely, but no increase in write amplification factor was measured.}},
  author       = {{Andersson, Markus and Hermansson, Filip}},
  language     = {{eng}},
  note         = {{Student Paper}},
  title        = {{Analysis of flash memory wear based on cache configuration and available memory}},
  year         = {{2023}},
}