[lkml]   [2014]   [Feb]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: locking changes in tty broke low latency feature
> This is a complete pointless test. Use a bog standard 8250 UART on the
> PC and connect a microcontroller on the other end which serves you an
> continous stream of data at 115200 Baud.
> There is no way you can keep up with that without the low latency
> option neither on old and nor on new machines if you have enough other
> stuff going on in the system.

Sorry but having done this in the past the reverse is true. On ancient
machines with crap uarts the low_latency case would routinely overrun
while the non low_latency case did not. That was half of the point of
deferred processing - it pushed tty processing out of the IRQ handler so
bytes were not lost and a 486DX could cope with a 56Kbit modem.


 \ /
  Last update: 2014-02-24 15:01    [W:0.104 / U:0.152 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site