This is great. We needed to do this stress-testing for a while now. It's also amazing how many of these small bugs weren't found when we never tried to reconnect.
Next project: I wonder if we can try upping the serial connection speed for the DS9097U. My tests indicate serial is slower than USB but uses less CPU time -- suggesting a lot of time waiting. My thought was to slowly up the speed, until bugs appear, them adjust speed over time based on recent success. There must be a good algorithm. Paul -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Christian Magnusson Sent: Tuesday, June 28, 2005 7:54 AM To: owfs-developers@lists.sourceforge.net Subject: RE: [Owfs-developers] More on "Hanging" Problems I feel pretty comfortable with the USB reconnection now. I started owhttpd and made a loop reading some files from an iButton. owhttpd -p 3333 -s 3001 owserver --foreground -u -p 3001 --error_level=1 -------- #!/bin/sh while [ 1 ]; do lynx --source http://172.20.1.122:3333/uncached/ > /dev/null lynx --source http://172.20.1.122:3333/uncached/02.6537C2000000/memory > /dev/null lynx --source http://172.20.1.122:3333/uncached/02.6537C2000000/pages/ident.ALL > /dev/null echo -n "." done -------- When I removed one iButton and really tried to simulate bad connection by moving it around close to the connectors, it failed in the BUS_select_low() and DS9490_reset() very often. I found some null-pointer bug when the usb-port was closed, but it reconnects all the time for me now. Hopefully it works when adapter hangs in other situations too. Could Jan test this version and tell us how it works for him... Some debug-output from owserver: (adapter reconnects at first attempt) ERR: USB DS9490 adapter reconnected (adapter tries to reconnect but fails) ERR: Error setting up USB DS9490 adapter at 004/002. ERR: Failed to reconnect USB DS9490 adapter! ERR: BUS_reconnect, returned error = -5 (at next read it reconnects with success) ERR: USB DS9490 adapter reconnected On Tue, 2005-06-28 at 07:31 +0200, Christian Magnusson wrote: > I agree... 3 attempts are perhaps not necessary. If it fails it should > only be necessary to try 1 attempt and then return "read-error", since > it's not possible to retry the old on-going operation anyway. > > I tried to start owserver to /dev/ttyS0 and then launch minicom on > /dev/ttyS0 too. This will trig the read errors at once since minicom > set the speed to 19200 baud and they will probably grab some chars > each... :) > > When minicom exits everything initialize and owserver works again. > I noticed one bug with oldSerialTio on COM_open() which should be > separate for each serial port though. > > /Christian > > > > On Mon, 2005-06-27 at 18:40 -0400, Alfille, Paul H.,M.D. wrote: > > Nice changes, Christian. > > > > I'm a little worried about burning CPU cycles if the adapter is unplugged. We > > will aggressively try to reconnect. > > > > I notice you make 3 attempts at reconnecting each time. That will be multiplied > > by the 3 attempts ar read/write. > > > > Would there be any harm in a delay before the 2nd and third reconnect attempt? 1 > > second? I suppose we could also allow a command line parameter to change that > > value for embedded systems where precisely tuning delays and utilization is > > important. Jan can offer some feedback on this. > > > > Paul > > > > -----Original Message----- > > From: [EMAIL PROTECTED] > > [mailto:[EMAIL PROTECTED] Behalf Of > > Christian Magnusson > > Sent: Monday, June 27, 2005 7:18 AM > > To: owfs-developers@lists.sourceforge.net > > Cc: [EMAIL PROTECTED] > > Subject: Re: [Owfs-developers] More on "Hanging" Problems > > > > > > > > Try the latest cvs again... I have fixed a missing > > usb_release_interface() and some other statistics from those errors. > > > > /Christian > > > > > > On Mon, 2005-06-27 at 11:34 +0200, Jan Kandziora wrote: > > > Am Montag, 27. Juni 2005 05:26 schrieb Gregg C Levine: > > > > Hello from Gregg C Levine > > > > Paul, explain this phrase in better detail please: > > > > "In any case, it's great that Jan has a setup where he can > > > > consistently trigger the errors." In an embedded an environment it is > > > > sometimes considered desirable to stress test the file system by > > > > triggering power cycles. There's an article on that, and the methods > > > > used somewhere on the Linux-MTD site. > > > > > > > What I do isn't stress-testing. That would mean to get parameters when some > > > component will probably fail and has to be replaced. That's not what I'm > > > after, at least at the moment. > > > > > > I just ran into that failure - it makes 1-wire completely unusable for my > > > application. > > > > > > > > > > Now I can see for myself how a rigged system would be desirable for > > > > stress testing the file system that we've created. But a detailed > > > > explanation would be good thing. > > > > > > > > Jan, what are you running? Which distribution? What is the hardware > > > > configuration? I walked into this meeting late, and left my agenda and > > > > most of my notes in a different location. > > > > > > > I'm designing a semiautomatic vending machine with a lot of attached devices > > > (flow-rate sensors and solenoid driven valves), most of them in a ten-meter > > > range around the machine, but some of them about 100m far away. The computer > > > which will be built into this will be a MIPS based embedded board, which > > > isn't completed yet. > > > > > > The computer I use to test is a Gene6310 "embedded" (more like barebone) PC > > > board. Its i386-family based. This computer is working and would be used as a > > > backup solution, if the MIPS board is not completed in time. > > > > > > I have a testbench, where I can arrange the devices like they were already > > > put into that vending machine. I hooked up the 1-wire to USB via a > > > off-the-shelf DS9490 adapter to the barebone. There is a mains transformer > > > 230/24V~ 150W (completely passive, not a switching one), which is the power > > > supply for the sensors and solenoids. The actual transformer for the machine > > > will be a 400W type, which makes things even worse. > > > > > > This mains transformer generates some kind of EMC when switching it "ON" or > > > "OFF" with an ordinary 230V switch. This is understandable if the switching > > > happens outside of the zero-cross of voltage (ON-switching) or current (OFF- > > > switching). The EMC pulse causes either the USB or the 1-wire (or both) to > > > disconnect - which leads owfs into an unusable state. > > > > > > I'm pretty sure I can minimize this EMC by putting a zero-cross and snubbing > > > circuit into my transformer - but I'm very unsure other appliances in the pub > > > or gas station where the vending machines will be mounted are so kind. > > > > > > That's why I think we have to be able to recover from this error > > > automatically. > > > > > > Kind regards > > > > > > Jan > > > > > -- > > Christian Magnusson <[EMAIL PROTECTED]> > > > > > > > > ------------------------------------------------------- > > SF.Net email is sponsored by: Discover Easy Linux Migration Strategies > > from IBM. Find simple to follow Roadmaps, straightforward articles, > > informative Webcasts and more! Get everything you need to get up to > > speed, fast. http://ads.osdn.com/?ad_id=7477&alloc_id=16492&op=click > > _______________________________________________ > > Owfs-developers mailing list > > Owfs-developers@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/owfs-developers > > > > > > ------------------------------------------------------- > > SF.Net email is sponsored by: Discover Easy Linux Migration Strategies > > from IBM. Find simple to follow Roadmaps, straightforward articles, > > informative Webcasts and more! Get everything you need to get up to > > speed, fast. http://ads.osdn.com/?ad_idt77&alloc_id492&opÌk > > _______________________________________________ > > Owfs-developers mailing list > > Owfs-developers@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/owfs-developers -- Christian Magnusson <[EMAIL PROTECTED]> ------------------------------------------------------- SF.Net email is sponsored by: Discover Easy Linux Migration Strategies from IBM. Find simple to follow Roadmaps, straightforward articles, informative Webcasts and more! Get everything you need to get up to speed, fast. http://ads.osdn.com/?ad_idt77&alloc_id492&op=ick _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers ------------------------------------------------------- SF.Net email is sponsored by: Discover Easy Linux Migration Strategies from IBM. Find simple to follow Roadmaps, straightforward articles, informative Webcasts and more! Get everything you need to get up to speed, fast. http://ads.osdn.com/?ad_idt77&alloc_id492&op=click _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
