On 7/29/09 11:47 AM, "Todd Lipcon" <[email protected]> wrote:
> On Wed, Jul 29, 2009 at 2:17 AM, Steve Loughran <[email protected]> wrote: > >> Scott Carey wrote: >> >>> Well, the first thing to do in any performance bottleneck investigation is >>> to look at the machine hardware resource usage. >>> >>> During your test, what is the CPU use and disk usage? What about network >>> utilization? >>> Top, vmstat, iostat, and some network usage monitoring would be useful. >>> It >>> could be many things causing your lack of scalability, but without >>> actually >>> monitoring your machines to see if there is an obvious bottleneck its just >>> random guessing and hunches. >>> >> >> iotop is very good here >> > > But sadly not available with kernels before 2.6.20 :( I was looking into > this recently and the next best thing I could find was blktrace, but it's > not nearly as nice. > > Any other tools people know about, especially that work on RHEL5/CentOS5? > Iftop worked for me for network traffic: http://www.ex-parrot.com/pdw/iftop/ For disk monitoring on CentOS/RHEL 5 Linux, every time I try and drill down a problem with iostat I wish I was on Windows or Solaris instead where monitoring and tracing disk I/O isn't a decade behind. On both of those, not only can you see what process is causing the disk activity, you can find out what FILES the activity is on. > -Todd >
