How to measure linux performance

Check with dd command in unix/linux systems... for example

#time dd if=/dev/zero of=/dev/null bs=1024k count=10000000
10000000+0 records in
10000000+0 records out
10485760000000 bytes (10 TB) copied, 359.587 seconds, 29.2 GB/s

real    5m59.615s
user    0m4.403s
sys     5m54.958s

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#ps