On 3/11/2018 7:39 PM, Deepak Goel wrote:
I doubt this. It would be great if someone can subtantiate this with hard
This seems to be in response to my claim that virtualization always has
overhead. I don't see how this statement can be at all controversial.
Virtualization isn't free, even if the hardware and software in use are
extremely efficient at it. Translating what a virtual machine does into
a corresponding action on the real hardware is going to take time and
resources beyond whatever the action itself is.
Plus there's the application-level overhead. You have the overhead of
multiple operating systems, multiple copies of Java running, multiple
servlet containers (probably Jetty), and multiple copies of Solr. And
each of them is running inside a limited subset of the hardware
installed in the physical server.
Let's say you start with VMs on a server, and benchmark Solr's
performance. Then you completely erase the server, install one
operating system, install Solr onto the OS, and then install all of the
indexes that were running on the VMs into that one Solr instance.
Assuming that things are set up correctly and that you give that Solr
instance the correct amount of heap memory, it's almost guaranteed to be
faster than the VMs. I can't tell you whether the improvement will be
half a percent or 50 percent, only that it will be faster.