I.MX8 plus eMMC write speed low

[BIlltu]

Hi.

 We had use I.MX8M and reload image of 30 time, Then use FIO tool to test eMMC R/W speed and find write speed from 150MB/s reduce to 30MB/s. We had check eMMC frequency keep 200MHz (pass and fail state) . So have any recommend to check point of issue and how to clear it.

 Bill

[Arvin]

I also encountered the same problem on the imx8mm evk board. The fastest sequential write of WD emmc can only reach 30M/s. How should I troubleshoot it?（I have tested the 4.14.98 and 5.15.71 versions of the image）

[BIlltu]

I had use I.MX8M EVK board to upload image and check write speed same as from 150MB/s to 30MB/s result. So this issue was happen on EVK board . Have you happen this issue?

[BIlltu]

HI

  I had use I.MX8M EVK board to upload image and check write speed same as from 150MB/s to 30MB/s result. So this issue was happen on EVK board .

        Bill

[garygong]

Hi Experts,

   Got the same issue on i.MX8MP evb with LF_v.5.15.71-2.2.0 image.  Using uuu for download image to evb. Image download become more slower after download image several time. Can anyone help on this issue?

Any suggestions would be highly appreciated.

[Carol2698hunter]

Hello BallSportsGear@BIlltu,

This seems to be a common problem for eMMC devices, especially when they are used for multiple write cycles. Several factors can affect the eMMC write performance, such as the file system, the driver, the firmware, the cache, and the wear leveling. 

Some possible solutions that you can try are:

• File System Optimization: Ensure your eMMC is using a file system optimized for fast writes, such as a journaled file system. You can also use tools like fstrim or discard to trim the unused blocks and free up space.
• Driver/Firmware Updates: Check for driver and firmware updates for your eMMC device. Updates might enhance performance, fix bugs, or enable new features. You can use the mmc-utils tool to query and update the eMMC firmware.
• Cache Management: Enable or disable the eMMC cache depending on your use case. The cache can improve the write speed by buffering the data, but it can also cause data loss or corruption if the power is interrupted. You can use the mmc cache command to control the cache.
• Wear Leveling: Avoid writing to the same blocks repeatedly, as this can degrade the eMMC lifespan and performance. You can use tools like badblocks or e2fsck to check and mark the bad blocks, and use the mmc extcsd command to monitor the eMMC health status.

I hope this helps you improve your eMMC write speed. 

Best Regards