You should be considering a few things: (1) Do you NEED the data that is consuming all of that space? There may be a lot of data that you WANT, but not that you need. And if you decide that you NEED it, make sure that you are making every use of the data. In other words, is there information about your business, market or customers that you can obtain from the data? Can you get a sense (2) If you need, all of the data consider the cheapest way to store it. In house servers, remote storage, compressed, the most recent X% of the data. If you have no budget for expansion or remote storage, get rid of the oldest 10% of the data simply to improve performance.
- Do you NEED the data that is consuming all of that space? There may be a lot of data that you WANT, but not that you need. And if you decide that you NEED it, make sure that you are making every use of the data. In other words, is there information about your business, market or customers that you can obtain from the data? Can you get a sense
- If you need, all of the data consider the cheapest way to store it. In house servers, remote storage, compressed, the most recent X% of the data. If you have no budget for expansion or remote storage, get rid of the oldest 10% of the data simply to improve performance.
With the case of an external hard drive where the OS is not present, you can safely use up most of the drive without noticeable performance degradation. For a hard disk with the OS, there are cache files whose size depends on the OS and the types of tasks that it performs.
For linux, check this out: How can I benchmark my HDD?
See these texts for more thorough exposition: http://www.amazon.com/Memory-Mass-Storage-Giovanni-Campardo-ebook/dp/B00F76KCGY/ref=sr_1_4?s=digital-text&ie=UTF8&qid=1420389894&sr=1-4&keywords=hard+drive+performance
