gnus: Agent as Cache
6.9.5 Agent as Cache
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When Gnus is plugged, it is not efficient to download headers or
articles from the server again, if they are already stored in the Agent.
So, Gnus normally only downloads headers once, and stores them in the
Agent. These headers are later used when generating the summary buffer,
regardless of whether you are plugged or unplugged. Articles are not
cached in the Agent by default though (that would potentially consume
lots of disk space), but if you have already downloaded an article into
the Agent, Gnus will not download the article from the server again but
use the locally stored copy instead.
If you so desire, you can configure the agent (see ‘gnus-agent-cache’
Agent Variables) to always download headers and articles while
plugged. Gnus will almost certainly be slower, but it will be kept
synchronized with the server. That last point probably won’t make any
sense if you are using a nntp or nnimap back end.
Info Catalog
gnus: Agent Visuals
gnus: Gnus Unplugged
gnus: Agent Expiry