D3 performance

Hi All

I'm new to D3 and am after some system maintenance and peformance
monitoring tips or guidelines... areas to check/poke around in etc

I've picked up a customer running D3/Linux, not sure of the versions at
this point, who's concerned about performance. They haven't done much
in the way of system maintenance themselves so we're probably looking
at file sizing as an obvious starting point, but beyond that what is
there on D3???

Are there logs to check, particular processes to monitor, config
settings to verify etc etc

Any relevant advice would be much appreciated.

Rgds
Juss

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