Similar to https://github.com/jellyfin/jellyfin/pull/10884
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Jellyfin clients need fonts for subtitles, and each font is a separate
attachment, which causes a lot of re-reads of the file. Certain contents,
like anime in a lot of cases, contain 50-80 different attachments.
Spawning 80 ffmpeg processes at the same time on the same file might
cause swapping on slower HDDs and can bring disk subsystem to a crawl.
(For more info, see https://github.com/jellyfin/jellyfin/3215)
This change helps a lot in this scenario.
Signed-off-by: Attila Szakacs <szakacs.attila96@gmail.com>
8d40d431e8