File system, RTEMS, RTOS, Software

Setting up YAFFS2 and JFFS2 on RTEMS with flash simulated on a RAM-disk

Hi all, In this post, we’ll look forward to setting up flash file systems namely JFFS2 and YAFFS2 on RTEMS with flash simulated on a RAM-disk. For file system benchmarking purposes, we didn’t actually use them on a real flash(as to eliminate the effect of flash driver’s performance) but implementing them on a real flash won’t be very different from the process given in the later sections of this post. So, let’s begin with JFFS2 first: JFFS2 on RTEMS First reference you will see is of testsuites/fstests/jffs2_support/fs_support.c . Configuration here works up to a large extent unless the size of…

Continue Reading

ARM, Benchmark, File system, FIO, GSoC, RTEMS, Software

Benchmarking RTEMS Filesystems using FIO

Hi, In this post we will explore FIO’s RTEMS port and how it can be used to benchmark RTEMS filesystems and drivers. First, let’s have a quick look at all the RTEMS filesystems: RTEMS FILESYSTEMS RTEMS supports mainly two types of filesystems: Network and Physical fs. Benchmarking support for networking filesystems isn’t yet available. However, nearly every other physical filesystem can be benchmarked and contrasted. Heap-based file systems are those which uses malloc() for file allocation. In other words, they reside completely on heap memory. These are mainly used to provide basic directory/file management even if there is no dedicated…

Continue Reading

Benchmark, CAM, File system, FreeBSD, GSoC, mmccam, SDIO

microSD Card benchmarking on BeagleBone Black

Hi all, I have been recently involved in benchmarking two different device drivers of FreeBSD ,namely SDHCI and the SDIO driver to compare their relative performance under different circumstances. Here, I will summarize my results, possible conclusions and the benchmarking procedure. Before moving towards benchmarking, i’d prefer going through this article. It really good and provides a great overview of how data is transferred to disk, different APIs available. This will surely help you selecting options for the benchmark. Benchmarking procedure I initially experimented with different benchmarks like iorate, iozone, fio, bonnie++ etc but the one i really liked was…

Continue Reading

File system, Hardware, NAND/NOR

Effect of file-system on sd card’s performance

I had a task to compare different protocols( and their different implementations) like SD, SPI, SDIO(in FreeBSD’s MMCCAM implementation) by accessing SD Card. Now, for unbiased comparison, I must eliminate file system type in sd card from the equation. In this blog post, I’ll discuss/share my findings of the file-systems used for the card(SD and MMC) and how they affect its performance. So, let’s start with a very quick introduction to some basic concepts: Introduction MMC- Multimedia Card is a memory card unveiled in 1997 by SanDisk and Siemens based on NAND flash memory. eMMC is a regular MMC in…

Continue Reading