I've update kernel 3.14.28 to 3.14.52 recently. I've connect hdd(2T) to sata interface.
but I've found performance degradation regardless which format have with sata hdd read/write test.
Result is HUGE degradation between 3.14.28 and 3.14.52. How to remove SATA degradation point ?
file system is based on ext4. bsp is commercial.
cpu : imx6dual
command : iozone -a -n 4096m -g 4096m -i 0 -i 1 -f /mnt/HDD1/iozone.tmpfile -Rb ./iozone
- 3.14.28 kernel : write 100Mb/s, read 120Mb/s
- 3.14.52 kernel : write15Mb/s, read 60Mb/s