Changes

Parts of such sections are retrieved from the White Paper ''TRACE32 log method for analysing accesses to an eMMC device'' by Lauterbach, which is freely available for download [https://www.lauterbach.com/publications/trace32_log_method_for_analysing_accesses_to_an_emmc_device.pdf here].

As stated previously, eMMC's and SD cards are block devicedevices. As such, they are operated in tandem with file systems that have been developed for hard disks and solid-state drives. [https://en.wikipedia.org/wiki/Ext4 <code>ext4</code>] is one of them and one of the most popular in the Linux world. On the one hand From system integrators' perspective, eMMC's and SD cards are easier to use by the systems integrators than raw NAND's because they hide most of the complexity regarding the management of the underlying NAND memory. On Nonetheless, the other hand, their architecture of these devices could make it difficult to retrieve data regarding the actual usage of the memory at low level. There are several some techniquesavailable, however, to address this issue when working with an embedded Linux platform. This sections will illustrate the following ones:* Logging the accessesto the storage device: The idea of this approach is to log all the accesses triggered by the host and isolate the write operations in order to determine the actual amount of data written onto the device. Two different methods are compared. The first one makes use of a hardware-based trace tool while the other exploits a software tracer, namely the Linux kernel's Function Tracer (<code>ftrace</code>).

In the following sections, these These approaches are illustrated in more detail in the rest of the section with the help of actual test results that . These tests were run on the [[MITO_8M_SOM/MITO_8M_Evaluation_Kit|Evaluation Kit]] of the [[MITO_8M_SOM|Mito8M SoM]]featuring a SanDisk SDINBDG4-8G-XI1 eMMC operated with an ext4 file system.