Rimuhosting and Swap Space
A note about swap space. The most helpful Peter Bryant of Rimuhosting says:
- Small swap. Intentional. VPSs that swap use lots of CPU and disk IO. Leads to high server load. Leads to poorer overall performance for everyone.
I agree, 99% of the time. However, apt-get and yum seem to be quite memory intensive, they build big tables in memory. If you do a whole distribution update with these tools, you will need a very large amount of memory, for a few hours, once or twice a year. If there was a way to purchase a few hours use of more memory for this process, then that would be the way to do it. However, since there is not, you can temporarily do a
- mkswap /swapfile ; swapon /swapfile
and use that, for major yum updates only. After you are done, do a
- swapoff /swapfile
so you are not thrashing the host machine. If your normal memory needs approach the maximum for your virtual machine, you should buy more. I typically use 46MB out of the 96MB I have paid for, and trim down the configuration files (principally Apache) if I run over that.
It would be best to do this at times of low host load averages, but without some sort of graph of uptime/downtime for the host, you will probably just have to guess the right time of day/week to do it.
The ideal would be to use some kind of Copy On Write process, with Rimuhosting providing an updated base distro, so you don't even have to worry about doing your own updates. Sadly, Xen doesn't have COW yet.