I run Serato on a similar MacBook as my backup MacBook (Core2Duo 2,2 GHz, 8 gig RAM, 500Gig 7.200rpm HD).
I have ZERO problems unless I assign the F/X unit badly or run the Pitch’n’time plugin.
The F/X are really the most demanding thing on CPU time, especially when you load/analyse a track that is not yet analysed in parallel to what you are doing.
From all the softwares I have tried (Serato, VDJ, Traktor, Cross) Serato is clearly on the lowest end of CPU demands.
So what I would recommend to you:
Analyse your tracks before the gig so that they are stored in the library.
Do not overuse Effects that use high CPU load (multiple delays at the same time).
Possibly route the F/X to master out as channel based F/X use more CPU.
Do not use F/X and analyse tracks at the same time.
Follow that and you should be OK.
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