Date: Mon, 6 Mar 2017 12:36:57 +0100 From: Markus Rechberger <mrechberger@gmail.com> To: Hans Petter Selasky <hps@selasky.org> Cc: freebsd-multimedia@freebsd.org Subject: Re: What is wrong with FreeBSD and USB Support Message-ID: <CA%2BO4pC%2ByGM3CwNgAsKAp3CQtdCFCPZ8fukG2aKK4oO3MU=VPfA@mail.gmail.com> In-Reply-To: <9fe561d0-3d8b-8725-98d4-37c2eb094ae9@selasky.org> References: <CA%2BO4pCK4%2B1rE5ft4Boy_3xPdCxK31UtTQ2BYpnBUn5jxZr%2Bz_g@mail.gmail.com> <CA%2BO4pCJr5Bq-sgjzvZQB-mFRT6x7Tp3psga6f__V9Ag-=v-mhw@mail.gmail.com> <CA%2BO4pC%2Bf5xzOjENKSJu_sQeaiN3XL3WiTcRQvm4vVweQ71Xtrg@mail.gmail.com> <CA%2BO4pC%2B1t67ODF7bkyVhcojXTLnFkS28RbFAc%2Be-tjNncogMAQ@mail.gmail.com> <CA%2BO4pCLRJRFG8Sv6C=FK6myBDPdUfhNjZ88P=e1uuH2=ojB75w@mail.gmail.com> <1aff0983-deb6-2884-472c-bb1e1037275c@selasky.org> <CA%2BO4pCLLSgdFOpJvnrD_F5Zh1aOGQexjiKKSiPbpcsKWs8wgUQ@mail.gmail.com> <CA%2BO4pCLvWi3hpLKfXiabQ6en0=PryXQC91tqeuj3VPCE8HQ_jg@mail.gmail.com> <9fe561d0-3d8b-8725-98d4-37c2eb094ae9@selasky.org>
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On Mon, Mar 6, 2017 at 12:30 PM, Hans Petter Selasky <hps@selasky.org> wrote: > Hi, > > On 03/06/17 11:53, Markus Rechberger wrote: >> >> 1. slow usb control messages - did you already noticed that? > > > From what I can see no USB control transfer completed no later than 1.555 > milliseconds. I loaded the numbers in the trace into a spreadsheet and got > the attached distribution. > > This is not slow. What times do you expect? > > The fastest XHCI can do is ~ 0.125 ms and from the analysis is appears that > the USB device is NAKing a little bit, causing the extra delay. > it's EHCI, but the driver needs 14 seconds to load everything with freebsd (ok there's a lot to send) but the other systems are all way faster with that (7 seconds max for initialising 4 chipsets). I somewhat think that this issue also has to do with the bulk latency killing the data transfer. Maybe the actual send is quick but maybe there's some additional libusb20 - usb userspace interface - usb - roundtrip problem that causes this high latency.
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