Hi all!
We've ran some CPU and RAM tests to compare the results:
- with OS installed directly on server
- with OS installed on a guest vm in ESXi which is installed on server
The results summary:
- CPU is 10-20% slower on VM
- RAM is 2-3 times slower on VM
Is it normal? Is there any official data on ESXi impact on CPU and RAM speed?
More test data follows:
- OS = ubuntu 12.04.2 LTS
- virtualization options enabled in BIOS
- phoronix-test-suite (pts) used as a benchmark
Test results
| Test | Direct result | Guest VM result |
|---|---|---|
| RAM (pts/stream) | ||
| Type: Copy | 97182.69 MB/s | 28319.06 MB/s |
| Type: Scale | 81834.49 MB/s | 26683.45 MB/s |
| Type: Add | 67717.94 MB/s | 26610.79 MB/s |
| Type: Triad | 66107.12 MB/s | 28359.80 MB/s |
| CPU (pts/java-scimark2) | ||
| Computational Test: Composite | 1216.39 Mflops | 1068.98 Mflops |
| Computational Test: Fast Fourier Transform | 767.54 Mflops | 656.84 Mflops |
| Computational Test: Jacobi Successive Over-Relaxation | 1176.41 Mflops | 1000.25 Mflops |
| Computational Test: Monte Carlo | 605.52 Mflops | 516.92 Mflops |
| Computational Test: Sparse Matrix Multiply | 1258.34 Mflops | 1099.83 Mflops |
| Computational Test: Dense LU Matrix Factorization | 2274.14 Mflops | 2071.07 Mflops |
Thanks in advance!