Hello, I have a pen drive and after running a benchmark, it says my pen drive has a write speed of only 1.1 Mb/s on average, against 13.5Mb\s of average read speed. I found the write speed surprisingly low and started to inquire myself if there could be something wrong with my linux distro (an ubuntu 10.04).
My personal experience says that the results of the benchmark are consistent with what I see on daily use.
You think it's worth try with another linux distro or is just it's flash memory that it is crap?

Thanks for any advices.

Could'nt hurt, you can even try that on a live disc...
Let us know what you find
Melissa

I tested on live disc and the performance seemed similar to the one informed by the benchmark (it was a slax distro and the file manager doesn't tell the average transfer speed).
I checked this site: http://usbspeed.nirsoft.net/ with hundreds of results, and no one has a result anywhere near 1.1Mb/s of write speed. If i didn't skipped any result, the slowest I saw was 2.96Mb/s , which is approximately 2.7 faster than mine. Very strange.
Maybe it's a defect, sometimes other computer can't read it's contents.

OK, here's my take on this. I've no idea how data is read or written to a USB pen drive but as a retired Computer hardware maintenance engineer I'll pass on a theory for consideration...

In the "bad old days" of magnetic media; disks, tapes, etc, reading data was just that, the data was read, moved to memory and manipulated, no state changes in media required. Writing data was different as, after the data had been written (with relevant "bit" state changes), it had to be read back and verified. This means that a write function also contained a read function hence it takes longer to carry out. Subsequently, the write function takes more processor cycles than a read one does.

Anyway, that's my thoughts. Non-static volatile memory is different as it requires refresh cycles to constantly read and write its cell states in order to maintain the data's integrity.

My

Play Bonny!

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Oftentimes, even the manufacturers will report speeds of i.e. 20MB/sec write and 60MB/sec read. The flash memory chips are just a great deal faster on write. When you read, there's no change to the data. When you write, it has to check for errors, manipulate bad blocks, adjust the write location for the sake of wear leveling, and (if you're not using FAT or ext2) it must write a journal besides.

Aaaah, takes me back to the days when you had to consider bits in order to complete a program...no much was done for you (no code completion, no backgroud safety nets, none of that) so it was the same cycle all the time idea -> paper -> writein (yes, more paper) out the code -> typing in -> saving (in case the code 'd lock up the system) -> crossing fingers -> running...
Aaahhhhh....where are the days....
Melissa

I've seen some flash drives that just won't work on a linux format.

Flash drives always have lower write speeds than read. Always. Yours is not that unusual.