Delay in python startup.
Chris Angelico
rosuav at gmail.com
Mon Sep 30 13:58:37 EDT 2019
On Tue, Oct 1, 2019 at 3:31 AM Tobiah <toby at tobiah.org> wrote:
>
> On 9/30/19 9:54 AM, Chris Angelico wrote:
> > On Tue, Oct 1, 2019 at 1:56 AM Tobiah <toby at tobiah.org> wrote:
> >>
> >> I don't have a lot of information, so here goes a shot in
> >> the dark. One day I started experiencing a delay when
> >> starting python. I'm on Ubuntu 16.04. It takes three
> >> seconds to get a prompt when I type 'python' on the command
> >> line (Python 2.7.12). When I run a script that imports
> >> packages, it takes longer, up to 17 seconds just to do
> >> the imports. Python3 is not affected, and is snappy as
> >> expected.
> >>
> >> That's all I know. I'm hoping someone else has seen this.
> >> I'm about ready to wipe the drive and upgrade to 18.04.
> >>
> >
> > Python 2 and Python 3 have completely independent installations, so it
> > could be a lot of things. First question: Does it take three seconds
> > *every* time you type 'python', or only the first time? If it's slow
> > the first time but then fast, it's probably just a matter of disk
> > caching; running Python 3 doesn't pre-cache the files for Python 2, so
> > you have to pay the load-time cost anew.
> >
> > If it's slow every time, though, you may have something messing with
> > your startup. Try "python -S" and "python -E" see if they're just as
> > slow. That would be a way to delve into things a bit.
> >
> > ChrisA
> >
> It was much faster with -S and instantaneous with -E. I had a directory
> in my PYTHONPATH that I mount with sshfs from a server. For some reason
> that mount is very slow. Thanks for helping me figure this out.
>
Cool! That would be it, then - every import had to go through that SSH tunnel.
Happy to help out.
ChrisA
More information about the Python-list
mailing list