Profiling Slowdown when Opening Message with Many Threads

[Cole Lyman]

Forgot to attach the profile.

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Cole Lyman <cole at colelyman.com> writes:

> Hi all,
>
> First of all, thank you so much to all of the developers that have
> contributed to notmuch. I think it is a beautiful piece of software and
> it has certainly made my life better.
>
> I have an email with about 16 threads (responses back and forth 16
> times, there are some pdf attachements thrown in there as well) that
> takes considerable time (30 seconds to a minute) to open up using the
> notmuch Emacs interface. As an aside, there are also some HTML emails in
> there which I have read could be the culprit.
>
> I have run the Emacs profiler and have attached the profiler report.
> From viewing the results from the profiler, it seems that there
> recursive calls to `notmuch-show-insert-thread` (one call for each
> thread, I presume) and as I follow the calls down the stack it turns out
> that the function `indent-rigidly` takes up 63% of the CPU cycles.
>
> Anyone have any insight as to why this is happening or next steps that I
> could try to debug this?
>
> I am running Emacs 26.1 (with Doom, in case that matters, in the call
> stack the `+mail/notmuch-show-reuse-buffer` is part of Doom) on OSX
> version 10.14.1. Please let me know if any other information would be
> useful!
>
> Thank you,
> Cole