I would record the kernel, and lspci, dmesg the hw/driver versions. You could be using different driver versions between the kernels. After that I’d look at the sysctl diffs between the two systems. Make sure the esxi resource entitlements and priorities are the same for each guest (which I’m sure you’ve already done, doesn’t hurt to double check).
Wondering if your using my drivers for ESXi (though I’m sure they’d be out of date by now, and depends on what your networking hardware is). -J > On Nov 20, 2014, at 5:33 PM, Jason Strongman <[email protected]> > wrote: > > > Hypervisor Version - ESXi 5.5 > Guest OS - Ubuntu 12.04.5 and 14.04.1 (64bit generic kernel) > > > While testing ATS in our Ubuntu guest VMs we noticed a significant > performance difference(for the worse) between another RHEL 6.5 VM. Both VMs > run in the same hypervisor and both VMs have the same 'hardware' specs. Both > VMs also received the same identical 5gbps Spirent performance tests. Each > test ensured that the tested objects are served from RAM cache. So it looks > like(just guessing) the RHEL kernel may be optimized for virtual environments > in terms of memory management?? > I do notice the library and compiler versions differ between the ATS > instances, the compile time options are the same. So I am not sure if that > may be prove to be an issue as well. > > That said, are there any OS tuneables that I should review within my Ubuntu > builds? > Next I am going to try the various Ubuntu kernels and see if that results in > the same RHEL performance. > > Thanks! > >
