2009/9/29 Pid <p...@pidster.com> > ... because for future requests, the data already exists and the work is > already done. The consequences of a dropped connection are therefore > reduced because you're not doing the work for every single request, and any > work you are doing isn't completely wasted.
Pid, you're assuming some features of the application that may not be true, namely that a sufficiently high proportion of the images are re-used for this work to be useful. If the cache hit rate is low, that assumption may well be false. You're also assuming that the resulting artifact is sufficiently lightweight that it is appropriate to cache. That, in turn, depends on the relative cost of generating the image vs storing it. On modern machines with very fast processors, modest amounts of memory and dreadful bandwidth to disk*, I'd not be willing to take either side of that bet without examining the application's resource profile in considerable detail. - Peter * Amdahl's Rule of Thumb: A machine should be able to clear its memory in one second and write it to disk in 10 seconds. For a general-purpose server, I think the rule still holds.
