Seeking clarification on "Write and read failure Input/output error" and overwritten

[ioogithub]

Hi, I am aware of the documentation here: https://fight-flash-fraud.readthedocs.io/en/latest/index.html however I have some questions about the results I am getting.

I am testing a new high performance sdcard. When using f3write I saw the following message:

WARNING:
The write error above may be due to your memory card overheating
under constant, maximum write rate. You can test this hypothesis
touching your memory card. If it is hot, you can try f3write
again, once your card has cooled down, using parameter --max-write-rate=2048
to limit the maximum write rate to 2MB/s, or another suitable rate.

Creating file 268.h2w ... Write failure: Input/output error
Creating file 269.h2w ... 27.92% -- 48.82 MB/s -- 4:40:37f3write: libflow.h:89: get_rem_chunk_size: Assertion `fw->blocks_per_delay > fw->processed_blocks' failed.

Then the app quit. The card was moderately hot. I continued the test and it completed.

When I ran f2read I see this:

Validating file 266.h2w ... 1683119/        0/      0/      0 - NOT fully read due to "Input/output error"
Validating file 267.h2w ... f3read: f3read.c:260: validate_file: Assertion `!fdatasync(fd)' failed.

The test also stopped again. I searched for the meaning of this message but did not find anything specific. I started the test again and again it stopped:

Validating file 367.h2w ... 1889324/        0/      0/      0 - NOT fully read due to "Input/output error"
Validating file 368.h2w ... f3read: f3read.c:260: validate_file: Assertion `!fdatasync(fd)' failed.

The card is not hot.

I also noticed this:

Validating file 355.h2w ... 2019086/ 0/ 0/ 78066

What does it mean that 78066 blocks were overwritten?

What is the implication of these collection of errors I am seeing, if the drive fake or otherwise defective? It seems like I cannot get though the read test without it erroring out.

Version: F3 Write 8.0.

[ioogithub]

I started a complete read operation again and this time it did not give me any IO errors here is the result:

I have one overwritten result:

Validating file 92.h2w ... 1990358/ 0/ 0/ 106794

and here is the final result:

Data OK: 953.36 GB (1999344166 sectors)
Data LOST: 52.15 MB (106794 sectors)
Corrupted: 0.00 Byte (0 sectors)
Slightly changed: 0.00 Byte (0 sectors)
Overwritten: 52.15 MB (106794 sectors)
Average reading speed: 105.04 MB/s

What are the implications of this considering the previous report? 54mb was lost? Does this indicate the card is slight fake or slightly malfunctioning?

I am using the original exfat filesystem settings that came with the card.

[AltraMayor]

I don't think your drive is fake, and I see these likely possibilities:

1. The drive had some issues and had to remap blocks. This is normal, all drives have to deal with this possibility. I think this is the most likely possibility. To validate this hypothesis, repeat the whole test, that is, rewrite the drive with f3write and f3read. It should come up without errors.
2. The card reader you are using doesn't dissipate heat well or is not working well. The best here is to buy a reader with a not-so-small metal body. Some readers may not get hot enough to the touch, but for the sdcard inside it could be too much to deal with under heavy load.
3. Sometimes a reader doesn't work well because the USB port is not stable. While this is the least likely possibility, this often doesn't have a fix and only comes up when the port is heavily used. You need another computer to test this possibility.

Good luck!