Hardware - Reliable and Fault Tolerant
Hardware Node Specifications?
In this business, performance is key, period. To continue to provide the best performing Semi-Dedicated experience for our customers, we recently went through a technology upgrade on all of our servers. Initially, we had deployed Intel Dual Xeon 2.8GHz and 3.06GHz 533FSB servers running RAID5 SCSI disk IO. While initially these were very fast machines, in the Semi-Dedicated business, they have quickly become outdated technology. After internal benchmarking and stability testing of newer hardware, we realized it was possible to deploy hardware nodes that performed anywhere from 1.5 to 2.5 times faster then the initial Intel Xeon 533FSB systems.
First, we looked at the CPUs. Intel released the newer Xeon product family last year, which has been upgraded to an 800MHz FSB and the CPUs now have double the L2 Cache at 1MB, as well as a faster memory subsystem. We have also been a fan of the AMD servers since they were released, and have used them internally for different customers and projects. Industry standard benchmarks show the AMD Opterons performing anywhere from 1.5 to 2.5 times faster then comparable Intel Xeon servers.
We stress tested the AMD servers to make sure they had the reliability required to host customer Semi-Dedicated servers. We worked with SWSoft (makers of Virtuozzo) on making sure the AMD kernels were stable and supported the newer AMD servers. At the end of the day, the AMD Opterons proved themselves in terms of performance and reliability, we were sold!
The next part of the server that needed performance improvements was the disk IO.
We started out using SCSI 10KRPM RAID5 solutions, and soon found out RAID5 is not best suited where you need blazing fast disk IO. RAID 5 has some of the slowest write speeds of any of the RAID technologies available. So, we tested different RAID technologies, and the end result was that the RAID10 subsystems provided the best disk IO for read and writes. It also provides the ability to sustain multiple drive failures, unlike RAID5. To increase performance even further, the disk IO benefits from more drives/spindles, so we now deploy our RAID10 arrays using 12 disks that are 10K RPM 74GB drives, with 2 disks as hot-standby. RAID10 is about double the costs of RAID5 per megabyte, but the performance benefits that our customers enjoy make it a worthwhile cost.
Backup technology. We deploy Dual Xeon servers attached to 2TB or greater disk arrays over a private Gigabit Ethernet network. Each hardware node has a private connection to this network as to not impact live customer network traffic. The disk arrays are setup as a RAID6 array with hot-spares. RAID6 allows for 2 simultaneous drive failures, offering the best redundancy option available. Make sure your Semi-Dedicated provider DOES NOT backup your data to the same hardware node that you are running on, as this offers zero redundancy if something should happen to the hardware node your VPS runs on, as well as degraded disk IO performance during the period your VPS backup runs.
The end result is that we are deploying the fastest hardware nodes available to run our customer Semi-Dedicated servers.The fastest CPUs (Xeon 800FSB 3.0 to 3.6GHz and Opteron 248 and 250 processors), 8Gig of DDR333 or DDR400 ECC Registered RAM, the fastest disk IO utilizing RAID10 disk arrays, the fastest network connectivity with 2xGigabit Ethernet connections per hardware node, and the fastest and most redundant backup solutions to near-line RAID6 protected servers.