Key ingredients to achieve effective 1/O asyne IOopt snact caching c/c More bad numbers Data size for decent efficiency Usage Speed Latency 50%efficiency 91%efficiency CC 1GBs-1 100μs 10kB 100kB CC 10GBs-1 100μs 100kB 1MB WAN 1GBs-1 10ms 1MB 10 MB WAN 10GBs-1 10ms 10MB 100MB UK-JP 10GBs-1 250ms 250MB 2.5GB Remember maximum TCP packet size is 64 KiB latency ac mig 9/57 S.Ponce-CERNKey ingredients to achieve effective I/O 9 / 57 S. Ponce - CERN async IOopt struct caching c/c latency async msgQ More bad numbers Data size for decent efficiency Usage Speed Latency 50% efficiency 91% efficiency CC 1 GB s−1 100 ➭s 10 kB 100 kB CC 10 GB s−1 100 ➭s 100 kB 1 MB WAN 1 GB s−1 10 ms 1 MB 10 MB WAN 10 GB s−1 10 ms 10 MB 100 MB UK-JP 10 GB s−1 250 ms 250 MB 2.5 GB Remember maximum TCP packet size is 64 KiB