On Fri, Sep 27, 2019 at 10:22:10PM -0500, Eric Blake wrote:
 On 9/15/19 9:55 AM, Richard W.M. Jones wrote:
 
 >The fun plugin is a reflection plugin which "reflects" client
 >information back to the client.  We have a few fun plugins like this
 >(hello there, nbdkit-full-plugin) and normally I would push these
 >without review, but in this particular case there's a specific danger
 >that sending back data under control of the client might lead to a
 >security problem.  I _believe_ I have avoided that pitfall, but my
 >belief isn't as good as having experts review it :-)
 >
 
 A thought for another potentially fun mode: what if the reflection
 plugin reports back connection uptime?  The disk would be a
 fixed-width size (maybe 8 bytes: uint32_t for seconds, uint32_t for
 nanoseconds), where the contents are always changing to record the
 delta in time between any given request and when the connection was
 first created (in this mode, multi-conn and caching contents is
 actually quite wrong). Back-to-back commands can in turn be used to
 measure connection latencies. 
Yes good idea - I sent a patch.  It needs a test which I can get
around to later.
Rich.
-- 
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