Hello, I've recently been battling a performance regression on my Wifi, until I figured out that it was a driver issue. To be precise, it's a regression introduced by this commit: iwlwifi: disable TX AMPDU by default for iwldvm, 205e2210daa975d92ace485a65a31ccc4077fe1a Predictably, setting 11n_disable=8 restores performance. Without it, my throughput falls by almost an order of magnitude to 802.11g levels! This can't be intended. Even as a trade-off for increased stability (which is what I understand this commit is for), this seems like a bad default. Additionally, it's very hard to diagnose (took me many hours). Can there be a better way?
I can't see another way. I can't really debug the FW issues and most people care more for reliability than performance.
For the record, TX AMPDU has been enabled by default for all devices since linux 5.1 due to the inadvertent reversion of commit https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=205e2210daa975d92ace485a65a31ccc4077fe1a in commit https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e78da25e19c2dd31018c358d0717e4f6cfe317c8.