Hi, I have been experiencing some odd behaviour (major slowdowns) in my laptop for some weeks now. After some investigation it turned out that hard disk performance was the reason. My buffered reads were way below the average when running hdparm -tT /dev/hda. However, this only occurred at some points in time. Since it was hard to reproduce I did not report the problem. Yesterday I have finally been able to narrow down the cause of the problem. This slowdown occurs if my cd-rom drive is open or if there is no disk in it. Even though I don't understand how this is possible, the figures from hdparm -tT /dev/hda follow: With a cd in the cd-rom drive (average of three runs): /dev/hda: Timing cached reads: 605.79 MB/sec Timing buffered disk reads: 29.90 MB/sec With the cd-rom drive open (average of three runs): /dev/hda: Timing cached reads: 594.06 MB/sec Timing buffered disk reads: 5.11 MB/sec With cd-rom drive closed but with no cd in it (average of three runs): /dev/hda: Timing cached reads: 593.94 MB/sec Timing buffered disk reads: 14.7 MB/sec My system is a Dell Inspiron 8200 laptop (P4M 1.9 Ghz, 1 GB RAM, Geforce 4 Go 64 MB RAM) and /dev/hda is a Hitachi Travelstar 7k60 (7200 RPM drive). I also have an external firewire drive that does not exhibit any of the problems mentioned. I'm using a fully updated Fedora Core 3 with a 2.6.10-rc2 kernel and KDE 3.3.1. I have experienced this problem with earlier kernels though. It is important to note that the current problem is _always_ reproducible. Has anyone experience a similar problem? Should I file a bug report and if yes, against what component? Thanks in advance. Regards, Ismael P.S. DMA is enabled.
