On Tue, Nov 18, 2008 at 3:58 PM, Filipe Brandenburger <filbranden at gmail.com> wrote: > Hi Rudi, > > On Tue, Nov 18, 2008 at 02:13, Rudi Ahlers <rudiahlers at gmail.com> wrote: >> ...which can't take a lot of load... >> ...the machine sky rockets at some times... > > The problem you have is that the Load Average is too high? > > If that is indeed your problem, there is no way that this can be a > memory or CPU issue, since those would cause crashes and not high Load > Average. > > If what you have is high Load Average, check this: > - Your machine has 8GB RAM. Are you using the 64-bit version of > CentOS? There would be an overhead in using a 32-bit PAE version on a > machine with more than 4GB, last time I tried it (some years ago) the > overhead was big enough to make a difference in the server's > performance. > - Your machine has SATA. If you don't use the correct SATA settings on > the BIOS, CentOS may use it in a backwards compatible mode and you > will not get enough performance out of it (see previous posts on > problems on SATA and on AHCI). If that's the case, changing the BIOS > settings might make a huge difference, but beware that if you do your > machine may no longer boot with the OS you installed right now. Better > thing to do would be to reinstall it once you found the right setting. > > And next time, please state your problem clearly ("high Load Average") > instead of jumping the gun and saying you have a CPU or RAM issue > which does not seem to be the case here. > > HTH, > Filipe > _______________________________________________ Hi Flippie, I have checked the BIOS settings, purely cause the new HDD was installed on a machine withou AHCI settings, so I had to change the settings in the BIOS to nativ IDE mode (the only other mode this motherboard supports). The reason why I'm suspecting the MB / RAM / CPU is that I already swapped the HDD's out, and reinstalled CentOS - first it was x64, now it's i386 (well, i686 as per uname -a). The only serivce that runs on the host node is HyperVM (which include the XEN tools, PHP, Apache, MySQL. I have the exact same setup on a few other machines, using Gigabyte motherboards + 4GB RAM. Other than that, the HDD's are the same, the OS is the same, and HyperVM is the same. I basically run yum upgrade once a week on all the machines. The only difference is this one has an Intel DG35EC motherboard with a Q9300 Quad Core CPU on it, which is supposed to be more power efficient than some of the Core 2 Duo CPU's on the other machine. As a matter of interest, all 5 Virtual Machines have been running on a Gigabyte motherboard + i6450 CPU + 4GB RAM since yesterday, and it's very very stable. So, my thinking is, it's the motherboard. It could also be the RAM, but I'm not 100% sure yet. The machine had 4GB initially, and then I added another 4GB hoping the problem would go away, but it didn't. -- Kind Regards Rudi Ahlers