[pacman-dev] [PATCH] Order downloads by descending max_size

[Allan McRae]

Here is my testing of this patch.

I picked 10 sets of 50 random packages from the Arch Linux repos:
pacman -Sql | shuf -n50

Then I cleared all caches, and ran:
pacman -Sddw --noconfirm

I ran each list 5 times, alternating between patched and unpatched
versions of pacman.  The medians of these five runs are:


Unpatched	With Patch
17		21
12		10
33		33
29		26
34		29
47		36
30		28
31		25
32		29
50		40

Expressing these as a percentage of the unpatched time (so less than 100
is an improvement):

124
83
100
90
85
77
93
81
91
80

For an average of 90% - meaning on average the downloads are 10% faster
when we order the packages.


This is obviously based on my connection, my mirror, and my choice of
parallel downloads (5), and with limited numbers of trials.  But as it
stands, I think accepting this patch will improve total download speed.

I will properly review the patch soon, with the aim to accept unless
contrasting results are provided.

Allan