Raspberry Pi 3 Model B v1.2 really slow

Question

My Pi has been running 24/7 for approx 3 years. Is it possible that it is just worn out?

I installed a fresh Raspberry Pi OS Lite on a brandnew Intenso Class 10 mircoSD. When I run apt-get update && apt-get upgrade the process will run for more than 6 hours, before I run out of patience.

Some people suggested it might be a fake SD so I ran f3 on it, these are the results:

$ f3write
Free space: 0.00 Byte
Average writing speed: 13.66 MB/s

$ f3read
  Data OK: 58.58 GB (122842048 sectors)
Data LOST: 0.00 Byte (0 sectors)
           Corrupted: 0.00 Byte (0 sectors)
    Slightly changed: 0.00 Byte (0 sectors)
         Overwritten: 0.00 Byte (0 sectors)
Average reading speed: 19.12 MB/s

I ran top but there was nothing suspicious: CPU idling at <1%, most of the memory free, swap unused.

Is there anything more I can try or should I just replace it with a new Pi?

Answer 1

You should check whether the f3 tests measure just sequential read-write or random read-write performance as well.

In most real use cases, random read and write performance is more important since it is the class of transfer operations being utilized when large amounts of files are copy/pasted or when software is downloaded and installed.

I have had bad experience with Intenso USB drives and SD cards in the past. While their sequential transfer operations are satisfactory and meet minimum specifications, it seems that random read-write performance is abysmal.

I have had to wait for nearly an hour to copy a large directory into Intenso's USB 3.0 32 GB USB stick. The same operation took a little more than 5 minutes on Kingston and SanDisk drives.

While I haven't used Intenso microSD cards for RPis, I did use them to boot and run Linux on an Intel Cyclone V SoCFPGA kit and ASUS Tinkerboard. Performance was sluggish and was remedied when I reverted to Transcend or SanDisk cards.

You will notice that while Intenso's USB drive and SD cards have a good average rating on Amazon, the top rated reviews are universally bad. Usual complaints include sluggish performance and bad reliability.

You can find quite a few bad reviews of Intenso products. In this video, a customer shares his experience with a microSD card. While I'm not sure if similar videos exist for cards, there are plenty of videos recording the benchmarks achieved by Intenso's USB drives. While some report satisfactory performance, others report horrible write performance. Here is one benchmarking video by a reputed German tech store.

In order to verify the performance of your specific microSD card unit, you can use a diagnostic utility detailed in the linked Raspberry Pi official blog, and check whether it satisfies target read-write operation thresholds.

Answer 2

It sounds like you've run out of free space:

$ f3write
Free space: 0.00 Byte

Linux expects some free space to always be available and may even fail to boot if you don't.

For a reference, here's what you could expect from a decent SD card (Samsung EVO, far from the fastest but OK):

pi@raspberrypi:~ $ sudo hdparm -tT /dev/mmcblk0

/dev/mmcblk0:
 Timing cached reads:   1266 MB in  2.00 seconds = 632.79 MB/sec
 HDIO_DRIVE_CMD(identify) failed: Invalid argument
 Timing buffered disk reads: 124 MB in  3.04 seconds =  40.77 MB/sec
pi@raspberrypi:~ $

So your card is still pretty fast, normally an update on a reasonably fresh image should take minutes, not hours.