This is completely true. The only reason that this looks faster is because the perl scripts are sleeping for 2 seconds. If they each had 2000 milliseconds worth of processing to do, running them in parallel would still leave you with 10 seconds of processor time needed. Parallelism doesn't magically give you more processors. Parallel processing is useful when you can compute lots of partial results simultaneously that can then be combined as inputs to another algorithm.

In reply to Re^2: Using perl to speed up a series of bash commands by transforming them into a single command that will run everything in parallel. by Anonymous Monk
in thread Using perl to speed up a series of bash commands by transforming them into a single command that will run everything in parallel. by tphyahoo

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