GNU bug report logs - #72339
Progress bars should not go backwards ever

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Date: Sun, 28 Jul 2024 16:02:38 +0000
From: "Zack Weinberg" <zack@HIDDEN>
To: bug-guix@HIDDEN
Subject: Progress bars should not go backwards ever
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I have noticed that when Guix is building derivations, the progress bar
for what it's currently building will often reverse to somewhere between
5% and 50% after reaching 100%.  In some cases, such as for guix-packages-
base.drv and guix-packages.drv, this happens several dozen times before
the build is actually complete.

This is a bug.  Progress bars should *never* go backward.  It is
actually better to have no progress bar at all than to have one that
gives a misleading sense of how close the operation is to completion.

zw