Hi all!
We've ran some 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 result is that RAM speed in guest is limited to ~27000 MB/s. Is this some kind of a hard limit? Can it be bypassed? 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 |
Server specs are:
| Component | Model |
|---|---|
| Processor | 2 x S2011 Intel Xeon E5-2560 (2.0 GHz, 20Mb, 8.0 GT/s, 8 Cores) |
| RAM | 12 x DDR-III 16Gb 1600MHz PC-12800 Kingston ECC Reg (KVR16R11D4/16) |
| Platform | Intel R2312GL4GS (2U, Grizzly Pass) |
| Storage | RAID10 consisting of
|
| Power supply | Intel FXX750PCRPS 750W Common Redundant Power Supply |
Thanks in advance!