DreamHost PS
From DreamHost
DreamHost PS or DreamHost Private Server is DreamHost's premium shared hosting service. Available as an add-on to an existing DreamHost plan, DreamHost PS uses Linux-VServer to create a "virtual machine" that protects a user's CPU and RAM resources from other users on the same physical machine.
Contents |
Features
- Protected CPU and RAM
- Ability to burst up to the full 2.3 GHz CPU and double the RAM
- Persistent processes are allowed (and will never be killed)
- 1 unique IP address is included
- Ability to alter the memory and CPU allocation on the fly, without the need to reboot
- Ability to reboot the server from the Control Panel
- Historical memory and load graphs can be viewed on the Control Panel
Important Note: If you order a PS, your entire shared hosting account is moved over to it, hook, line, and sinker.
(paraphrased from the DreamHost Blog Post that announced DreamHostPS comments' section - see comment #29)
Persistent Processes
Unlike the regular shared hosting setups, the Dreamhost PS allows for persistent processes to run. Regardless of how long it takes to run these processes (web invoked, console invoked, cron, or otherwise), the processes will never be killed by the server. It should be noted, however, that they are subjected to both CPU and RAM throttling.
In regards to the latter (CPU and RAM throttling), it seems from practice that when a process begins running, it will consume the level of RAM or CPU that it feels necessary. Although your PS may be confined to 150mb RAM / 150 MHz CPU (as an example), it is possible to exceed this number, though only briefly. As soon as the system is 'aware' that you have exceeded your maximum allowable commitment, the process will be throttled accordingly. In many cases, even though the process will continue to run, it may run VERY slowly. You may therefore discover that custom scripts will still run, but instead of taking seconds to complete, they may take several minutes.
Dynamic Server Settings Adjustment
Many of the key configuration options for your DreamHost PS server are configured on the fly by our automation system to best take advantage of your available server resources. For instance, if you have a 150MB PS server Apache will be configured to use a relatively small amount of memory, and if you have more memory it will be configured to use more memory. Currently this is handled automatically for key Apache settings and it will be extended to other configuration options over time.
