On Dec 5, 2010, at 9:26 PM, Adrian Crum wrote: > --- On Sun, 12/5/10, Adam Heath <doo...@brainfood.com> wrote: >> Again, why are people pushing back on this? It hurts >> no one, and >> could find cases where caching actually would help. >> Really, what is >> the harm? > > I can only speak for myself. I push back on entity caching stuff because I > feel it is redundant. Database systems cache data. Those database systems run > on top of operating systems that cache data. It seems to me that it's > redundant to cache data entity data at the application level. I'm not an > expert on the subject, I'm just suggesting that caching optimization should > be done at a lower level. Entity caching seems to me to be a form of > premature optimization.
There is a lot of value of caching on the app server for frequently used or performance sensitive data where stale data isn't such a concern. For most caches the whole point of the cache is to keep the data as close to where it is used as possible so that it is cheaper/faster to get. For example caches built into hard disks don't make much sense from that perspective. However, really caches built into hard disks serve a different purpose such as read-ahead buffering and such as opposed to caching data that has already been read just in case it is read again (which operating systems do for certain things, databases for other things, and app servers for others, as they should... and hard disk caches shouldn't). -David
