Slow SD Card?

[quadomatic]

I just benchmarked my SD card, and the result seems a little slow...

aneesh-openpandora:~$ dd if=/dev/zero of=/media/EXTREME/test.file bs=1M count=256

256+0 records in

256+0 records out

268435456 bytes (268 MB) copied, 70.337 s, 3.8 MB/s

This is a Sandisk Extreme 8GB card. It was benchmarked by Tom's Hardware as being much faster than that...maybe I need to reformat?

 

[I8NY]

test it on the pc because the pandora can only read and write so fast. (it should be faster than 4mb) if u get the same results on other pc/devuces then it is the card. reformat it and if that doesn't work u may have gotten a knock off.

 

[singler]

try using bs=32768


my Sandisk Extreme (class10, 16GB) writes >10MB/s (into ext2 partition, partition's block size is 4KB) and my Sandisk Ultra (class 4, 32GB) writes > 4MB/s (into FAT32 partition, cluster size 32KB) using dd 32k block sizes

 

[quadomatic]

I think it was an issue with formatting. I had tested it in xbench on my Hackintosh, and I was getting a really low benchmark score too. I then reformatted the card with Panasonic's SD card formatter, and it got a bit better. I'll try it again after I finish copying files to it again.

 

[quadomatic]

I'm getting a 13 MB/s write rate now, using bs=32768

 

[quadomatic]

I'm curious if SD card throughput was effected by this update.


Anybody else with HF5 test it out?

 

[Christoph.Krn]

I just benchmarked my SD card, and the result seems a little slow...

Although there can be (and likely are) other factors which may decrease the speed that your SD card is able to reach in this quick and non-empirical test, here's some information that might clear some things up for you (especially since you mentioned that using the Panasonic SD card formatter on the card has improved(healed?) its status): flash based storage (particularly SD cards): lifespan, speed, data safety, reliability and similar considerations.