[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Concurrency via isolated process/thread

From: Dmitry Gutov
Subject: Re: Concurrency via isolated process/thread
Date: Mon, 10 Jul 2023 17:53:20 +0300
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.11.0

On 09/07/2023 11:41, Eli Zaretskii wrote:
From: Ihor Radchenko<yantar92@posteo.net>
Cc: Po Lu<luangruo@yahoo.com>,emacs-devel@gnu.org
Date: Sun, 09 Jul 2023 07:57:47 +0000

Eli Zaretskii<eliz@gnu.org>  writes:

When programmers write such code for other interactive programs, they
are comfortable with the limitations of running code outside of the UI
thread.  Why should writing new, thread-safe Lisp for Emacs be any more
Because we'd need to throw away 40 years of Lisp programming, and
rewrite almost every bit of what was written since then.  It's a huge
setback for writing Emacs applications.
May you please elaborate why exactly do we need to rewrite everything?
We already did, please read the previous messages.  In a nutshell:
because most of the Lisp code we have cannot be run from an async

IME most of the code we have works decently already, and what we've been missing is a way to speed up certain crunchy bits without spawning an additional Emacs process (with all the coding pain and overhead that that entails). Workloads, for example, like creating a buffer (pinned to the thread), calling a process (asynchronously or not), getting JSON from it, parsing said JSON, processing the result, and returning it in some shape to the parent (probably main) thread. Most of the work that Gnus does, I think, also fits in that rough category.

Reporting on progress can be done by sending messages to the main thread, either via a dedicated mechanism ("messages" like in JavaScript Workers), or by changing some global variable as decided by the code author. The variable access would have to be synchronized, of course.

The worker thread will need an efficient way to return the computation result too (which still might be large, memory-wise), though. Maybe it'll use the same communication mechanism as progress report, maybe not. But it's something to keep in mind.

reply via email to

[Prev in Thread] Current Thread [Next in Thread]