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From: Peng Yu <pengyu.ut@gmail.com>
Newsgroups: gnu.bash.bug
Subject: Performance bug of {1..1000000}?
Date: Sat, 7 Mar 2020 10:39:36 -0600
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See the following run time comparison. {1..1000000} is slower than
$(seq 1000000).

Since seq involves an external program, I'd expect the latter to be
slower. But the comparison shows the opposite.

I guess seq did some optimization?

Can the performance of {1..1000000} be improved so that it is faster
than $(seq 1000000)?

$ time builtin printf %.sx {1..1000000}  > /dev/null

real	0m2.614s
user	0m2.361s
sys	0m0.166s
$ time builtin printf %.sx $(seq 1000000)  > /dev/null

real	0m1.516s
user	0m1.317s
sys	0m0.158s

-- 
Regards,
Peng