On 01/02/2008 01:53, Jerry Geis wrote: > Hi all, > > I used to use centos 4.5 on an AMD 4800+ with 2GIG ram. > Now I use centos 5.1 on AMD 6400+ with 4GIG RAM. > > The system responsiveness is different between the two. > I noticed that centos 5.1 seems to be swapping programs out > of memory at times resulting in slowness (perceived by me). > > I played with swappiness (/proc/sys/vm/) setting to 10, then 1 then 0. > Still resulted in the same perceived slowness. > Today I did swapoff -a and now the system obviously does not swap > anything out all all. I thought thats what swappiness of 0 would have > done. > > Are others experiencing this also? The perceived slowness maks the older > system with less RAM and slower CPU "seem" faster. > > Any suggestions on other things to try? > > Jerry Large amounts of swap "in use" does not necessarily reflect a system that is swapping heavily, and your perceived slowness may have another cause. Take a look at the output of "vmstat 10" command's swap columns for real time or "sar -W" for historical information regarding the number of pages being swapped in and out. These numbers will give you a much more accurate picture of how much swapping is occuring on your system. Cheers Luke