On Tue, Sep 30, 2008 at 4:54 PM, Michael Torrie <[EMAIL PROTECTED]> wrote: > When the load is high, the first thing to check is the amount of swap > being used. If the swap is exceeding 50%, I've found that Linux tends > to thrash a lot. In this case adding RAM will help, although if this is > not a normal server condition, maybe you have a process with a memory leak.
We suspected this, of course, but it appears that swap is not in use. SwapTotal == SwapFree means what I think it does, doesn't it? > If not, then check your disk i/o stats. If the disk is maxed out, or > even in action the majority of the time, then your load average is due > to disk wait, which is a hard one to solve. Sometimes a better i/o > scheduler can improve things. Sometimes faster disks. How do we check these stats? > If it's none of these things, then perhaps it's the network that > processes are waiting on. This isn't necessarily a bandwidth issue > either. If NFS is slow, the load average will shoot up, for example. What tools can I use to see if network is bottlenecking here? I doubt that's it but if it's not disk IO then I do need to check there. > So load is caused by I/O problems, whether disk or network. Can it also be caused, for instance, by an apache thread waiting for mysql to respond? If so then how do I tell if that's the case? /* PLUG: http://plug.org, #utah on irc.freenode.net Unsubscribe: http://plug.org/mailman/options/plug Don't fear the penguin. */
