I was running a multi-threaded program that makes huge amount of I/O operations, Basically reading/writing Millions of files. I had some problems/bugs and I used to halt the program to fix something and then run again.
Now the problem is after sometime everything went extremely slow, What are the possible reasons for the unexpected slowness? Could it be bad sectors? or problems with the filesystem?
I tried to copy the data to an external drive and the approximated time was 350 Hours!! with a speed of (4 kB/sec).
File System : Ext4
Platform : Ubuntu 13.04