Re: slow startup of zsh (1x slower than bash)

[Peng Yu <pengyu.ut@xxxxxxxxx>]

Not on my machine.

$ ./main.sh
time ./script.bash

real    0m0.719s
user    0m0.264s
sys    0m0.324s
time ./script.zsh

real    0m1.295s
user    0m0.360s
sys    0m0.680s

==> main.sh <==
#!/usr/bin/env bash
# vim: set noexpandtab tabstop=2:

set -v
time ./script.bash
time ./script.zsh

==> script.bash <==
#!/usr/bin/env zsh
# vim: set noexpandtab tabstop=2:

time for ((i=0;i<100;++i))
do
    /usr/local/bin/bash --norc --noprofile -c exit
done

==> script.zsh <==
#!/usr/bin/env zsh
# vim: set noexpandtab tabstop=2:

time for ((i=0;i<100;++i))
do
    /usr/local/bin/zsh -fc exit
done


On Fri, Dec 7, 2018 at 10:14 AM Julien Nicoulaud
<julien.nicoulaud@xxxxxxxxx> wrote:
>
> I don't think so, zsh is faster than bash for me without rc files:
>
> ❯ repeat 5 { time bash --norc --noprofile -c exit }
> took 0,011s (100% cpu)
> took 0,011s (98% cpu)
> took 0,011s (100% cpu)
> took 0,011s (100% cpu)
> took 0,011s (99% cpu)
> ❯ repeat 5 { time zsh -fc exit }
> took 0,002s (89% cpu)
> took 0,001s (90% cpu)
> took 0,001s (92% cpu)
> took 0,001s (92% cpu)
> took 0,001s (91% cpu)
>
> same with rc files:
> ❯ repeat 5 { time bash -c exit }
> took 0,028s (89% cpu)
> took 0,022s (100% cpu)
> took 0,022s (100% cpu)
> took 0,022s (100% cpu)
> took 0,023s (99% cpu)
> ❯ repeat 5 { time zsh -c exit }
> took 0,008s (91% cpu)
> took 0,008s (92% cpu)
> took 0,007s (92% cpu)
> took 0,007s (92% cpu)
> took 0,005s (91% cpu)
>
> Julien
>
> Le ven. 7 déc. 2018 à 03:57, Peng Yu <pengyu.ut@xxxxxxxxx> a écrit :
>>
>> On Thu, Dec 6, 2018 at 8:20 PM Sebastian Gniazdowski
>> <sgniazdowski@xxxxxxxxx> wrote:
>> >
>> > On Mon, 3 Dec 2018 at 17:28, Peng Yu <pengyu.ut@xxxxxxxxx> wrote:
>> > >
>> > > Hi,
>> > >
>> > > The following example shows that zsh startup time is much slower than
>> > > other shells. Can this be improved to at least as fast as bash?
>> > >
>> >
>> > Is it the last zsh version that's being tested? There was 2x startup
>> > improvement at 5.4 or something like this.
>>
>> Here is the version. I have not set up zsh to do anything fancy. I
>> guess the slowness of startup is because zsh does too many things
>> upfront and has more features than other shells, and the increase in
>> startup time the price that zsh has to pay.
>>
>> $ zsh --version
>> zsh 5.6.2 (x86_64-apple-darwin17.7.0)
>> $ cat ~/.zshrc
>> # Lines configured by zsh-newuser-install
>> HISTFILE=~/.histfile
>> HISTSIZE=1000
>> SAVEHIST=1000
>> bindkey -e
>> # End of lines configured by zsh-newuser-install
>> # The following lines were added by compinstall
>> zstyle :compinstall filename '/Users/pengy/.zshrc'
>>
>> autoload -Uz compinit
>> compinit
>> # End of lines added by compinstall
>>
>> > Also, Zplugin can load plugins after prompt, I load 20 plugins, and my
>> > startup times are:
>> >
>> > repeat 5 { time /usr/local/bin/zsh-5.6.2-dev-1 -i -c exit }
>> > /usr/local/bin/zsh-5.6.2-dev-1 -i -c exit  0,09s user 0,04s system
>> > 117% cpu 0,111 total
>> > /usr/local/bin/zsh-5.6.2-dev-1 -i -c exit  0,10s user 0,05s system
>> > 119% cpu 0,130 total
>> > /usr/local/bin/zsh-5.6.2-dev-1 -i -c exit  0,11s user 0,05s system
>> > 121% cpu 0,129 total
>> > /usr/local/bin/zsh-5.6.2-dev-1 -i -c exit  0,09s user 0,04s system
>> > 115% cpu 0,119 total
>> > /usr/local/bin/zsh-5.6.2-dev-1 -i -c exit  0,09s user 0,04s system
>> > 117% cpu 0,109 total
>> >
>> > I even load prompt after a default prompt, ~ 100 ms after it. The
>> > Star-Trek console-like impression this gives can be visible here:
>> > https://asciinema.org/a/156726 – much is going on, automatically, in
>> > background.
>> >
>> > > --
>> > > Regards,
>> > > Peng
>> >
>> > --
>> > Sebastian Gniazdowski
>> > News: https://twitter.com/ZdharmaI
>> > IRC: https://kiwiirc.com/client/chat.freenode.net:+6697/#zplugin
>> > Blog: http://zdharma.org
>>
>>
>>
>> --
>> Regards,
>> Peng



-- 
Regards,
Peng