I have been working on 2 vdr computers, both using raid and last night I noticed a problem. I saw the drive light was on steady shortly after I updated xine. So I checked to see if there was a problem and found the video was freezing for 10-20secs every 10-20 secs. I logged in through ssh and found the system very un-slugish. I it's once a month that mdadm checks the drives to make sure they are in sync. I stopped vdr/xine/x and it was still very slow to respond. It's an Athlon64 x2 and was still at 1000Mhz (lowest speed) with the operation using ~64% cpu. Since these cpus also slow down the bus as low speed, I changed the up point from the default 95% to 50%. But I don't know how much that will help. It was late so I wait till today to make the change.
This resync operation had an eta of ~75 minutes. What I'm wondering is how much it would effect any recording vdr might be doing when that starts? Clearly it messes up xine/vdpau. The array on that computer is 2 sata drives each with 3 partitions creating 3 raid1 arrays.