The best replacement for clustering is load balancing.

The best alternatives to clustering are rated as following:
★★★★★  load balancing
★★★★  classification
★★★  mirroring
★★★  mapping
★★  replication
★★  virtualization
★  fixed effects
★  nlb
★  webbing
★  sharding
★  segmentation
★  database mirroring
★  partitioning
  discriminant analysis
  network load balancing
  linux clustering
  non clustering
  decision trees
  brainstorming
  mirroring sql server

Your alternative for clustering is not listed? Suggest!
Speaking about clustering, one probably shouldn't forget about r.

Other search terms related to clustering and their ratings are:
★★★★★ r
★★★ shared storage
You have in mind a companion for clustering and it is not yet here? Propose!



Google Trends

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clustering
load balancing
classification