Comment 129 for bug 119730

Hi all,

I was moving disks around on my motherboard because the SATA cables blocked a video card. Two disks were placed on a secondary SATA controller on the motherboard which I hadn't used before. This has caused the slowness to resurface, with the mainline kernel.

Previously, all the disks were on an "82801IR/IO/IH (ICH9R/DO/DH) 6 port SATA AHCI Controller", using driver "ahci", capabilities "storage msi pm bus_master cap_list emulated", configuration "driver=ahci latency=0 module=ahci". According to lshw.

In the rearrangement, two disks were placed on a "JMicron 20360/20363 AHCI Controller", also using driver "ahci", capabilities "storage pm pciexpress bus_master cap_list emulated", configuration "driver=ahci latency=0 module=ahci".

Before installing mainline, there was both IO and overall system lag with the Intel controller. With mainline, the Intel behaves fine, but the JMicron turns out to be slow. (To the point where I personally consider it broken.)

I hope this info helps!