Am 11.06.2014 13:52, schrieb thegeezer: > ok baffling. > sdc i already said would be slower but not this much slower > it certainly should not be slower than the lvm that sits on top of it! > i can't see anything in the cgroups that stands out, maybe someone else > can give a better voice to this. > > all i can think is there is other IO happening > in atop if you can highlight any line that begins LVM CPU or DSK and > paste it in to a reply - with no virtualmachines running and no dd or > anything. > then run a dd as before and highlight the lines in atop while it is > running (maybe increase count to 1000 to give yourself a chance) and > paste in here too
I did a test with a sysresccd from 2013 (that is kernel 3.4.52 ... phew) Just booted, "vgchange -ay" and then the dd-test from LV to /dev/null -> with or without count=500 I get around 340-350 MB/s ! So my kernel-config seems buggy or I should downgrade to something older? Aside from that I checked the firmware of the controller, it has the latest release. Stefan
