Discussion of performance mounting new SSD that came with exFAT

Installing and Using OpenWrt
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I got a new USB 3.0 Samsung T5 2TB SSD while it was on sale ($190) and now using it as a networked drive for backup and movies archive (Kodi using Chromecast with Google TV). Oddly enough it came natively formatted with exFAT.

I mounted on OpenWrt 21.02-rc3 which comes with kernel 5.4. It works great with almost no effort, just installed the exFAT driver and enabled it in Samba4, getting about 120 MB/s read-write. CPU utilization isn't too high and regular routing with SQM cake, wifi, etc works as it should.

This is roughly the same performance I get on my old external USB 3.0 5400rpm drive which was 110-120 MB/s on OpenWrt, and that one is even formatted NTFS (mounted with NTFS-3G driver). But overall responsiveness is of course improved.

Anyway... given that performance is maxing out the gigabit LAN, should I bother reformatting this to ext4 or f2fs? Or just leave it exFAT since it seems to be working great, and it would be easier to unmount and use on my Windows 11 PC build.

I noticed exFAT is now natively supported in Linux kernel 5.4, hopefully this is the driver that is installed and that's why it's working well.

For reference, my OpenWrt router is the WRT32X. Linux kernel 5.4 exFAT link:
https://www.phoronix.com/scan.php?page=news_item&px=Linux-5.4-Released

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In this case exFAT's main drawbacks are the lack of journalling, and posix file permissions, and (sym)links. If you only use the disk only for network storage, the posix file permissions and (sym)links are probably a non issue. Journalling is another thing. It protects you against filesystem corruption on power outage, or 'unsafe' disconnection.
I have no experience with that large exFAT volumes, but I can imagine you can't repair a corrupted filesystem on the router itself, due to lack of memory.
Ext4 and NTFS both use journalling, and are better protected against filesystem corruption. (And if they get corrupted, it usually takes a lot less time to repair it).
The main advantage of f2fs is that it has build-in wear leveling. I doubt if that matters on an SSD, as a modern SSD does wear leveling itself.

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