JUQUEEN - Prace Training Portal

Thread Level Speculation (TLS)
• Parallelize potentially dependent serial fragments
– runtime creates threads for each speculative section
– threads run parallel and commit in order if no conflict
– on conflict, all threads except current master is rolled back
• Performance governed by tradeoff of overhead and
conflict probability
• Number of times to try rollback before non-speculative
execution can be set
• Hardware Limitation: maximum of 16 domains
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