On Fri, Jan 16, 2009 at 3:41 PM, Artem Kachitchkine <Artem.Kachitchkin at sun.com> wrote: > On 01/16/09 12:24, Patrick Arnoux wrote: >> I have run across this quote a couple of times : >> "Almost all USB-serial (Even ExpressCard) have speed >> limitations on Linux/Solaris due to a cap on the driver. (512k/s)" >> Using a Sierra 881 HSDPA modem on a TP61p, I get somewhat upside down >> throughput >> figures doing a speed test -- Download : ~400k/s Upload : ~1200k/s. >> >> Would someone be able to shed some light on this Cap feature and the >> implications of >> removing it / patching the code. > > I designed USB serial interfaces for Solaris and wrote a few drivers and > I'm not aware of any such thing. The driver always propagates data to > the application as soon as it receives it; same for transmit. If there > is any artificial capping at all, it must be on the device side.
Please. With Windows and Linux, I could get something like 300-400 Kbytes/second using a Pantech PX-500. The best I ever saw on Solaris was on the order of 100Kbytes/second. There's a constraint there, but I'm not sure what it is. Perhaps there's something like the composite packet issue that I saw in the zyd driver (which has been fixed privately and I'm waiting for source, and supposedly in the zyd driver that should be released in B107) Ben
