As part of our tests, we investigated whether adding another virtual network adapter would improve system performance, but we saw no improvement. We likewise didn't see any better performance in our SQL Server tests when we increased system memory, because the test is disk-bound.
While manipulating available resources made a difference in testing a single VM instance, VMware's resource-allocation capabilities give admins a way to allocate only a finite amount of CPUs, CPU cycles and memory.
Our baseline test hardware included two dual-core 64-bit Xeon processors running at 2.7 GHz. ESX Server let us allocate this only in terms of 32-bit processing power, meaning that while ESX Server could execute 64-bit code to manage VM environments, the VMs could run only 32-bit OSs and applications. To be clear, ESX Server does support 64-bit OSs, so you can deploy 64-bit apps under VMware. In our tests of 32-bit apps running on 32-bit versions of Windows Server 2003, however, ESX Server let us allocate processing only in terms of 32-bit processing power. When we tried installing the 64-bit version of Windows Server 2003, Windows identified our virtual processor as a 32-bit processor.
Furthermore, available resources included a representation of actual CPU MHz. In theory, we had cycles we could divide up across VMs. The number of processors is more flexible: We could create machines with more than four processors that would correspond to the four theoretical processors available in two dual-core processors.
Although we could add network cards to VMs, ESX Server doesn't support dynamically allocating drive space to a system except through a connected storage device. From a practical standpoint, this was the most problematic area we encountered in our tests. The size of a VM image, which includes disk space, could be the determinant factor when it comes to deciding the number of VMs that can run on a given system. ESX Server, by default, allocates 4 GB of disk space for a VM. On our test system, we allocated a minimum of 10 GB, just to ensure we had enough room to install apps and to allow for the impact of patches over time. On our system, with 128 GB of drive space, we had enough space for 10 VMs.
Bob Friday, Chief AI Officer for Juniper Networks, explains how the advanced technology is transforming operations.
Contact center leaders from 8x8, Awaken Intelligence, and 360insight discuss the importance of agent experience.
AI may force enterprises to rewire parts of their data centers so they are fully optimized to run such workloads. The question is do you use Ethernet or InfiniBand?
