A Spotlight importer is called upon as files are created, copied, and modified, so performance is crucial. Importers should be able to extract metadata from documents quickly and with minimal effort.
Avoid burying metadata deep inside a file, especially if finding that metadata would be computationally intensive later. If needed, define your file format so that relevant information is in the header or in an easily accessible location.
It is also vital that your importer does not leak memory, as this can contribute to performance problems.
Last updated: 2009-10-11