By default, when the
is started, all its caches are empty. In a test or development
environment, where activity is usually very low, this is not a problem.
For a production system running a busy site, however, the level of
requests can be so high as to completely cripple the site if all requests
have to be fully processed rather than served from the cache. For this
InitialBootstrapper component that can be
used to protect the
from traffic during start-up, allowing it to prime the caches with
frequently-requested pages before it is required to respond to real
InitialBootstrapper component works by:
Intercepting incoming requests and returning HTTP 503 responses (Service Unavailable).
Simultaneously submitting a series of dummy requests for frequently requested pages, thereby priming the caches with content that will enable fast responses to many requests when the bootstrap sequence is completed.
Bootstrapping is initialized on a per-publication basis by setting the
parameter in each publication's
feature resource. The
bootstrapOnStartup parameter allows you to specify the
individual sections of a publication that are to be bootstrapped.
Details of how the
carries out the bootstrap operation can be controlled by setting
properties in the
configuration file, described in the following section.