Ok because of the long thread a short summary: My transferrate tests were running on a normal IDE device.
VIA IDE, USB and so on ... systems are intefering. USB-system affects IDE system, sometimes in a dramatic way (diff. 20MB/s on IDE transferrate). Beside this sometimes the ehci-driver disconnects USB devices without any reason. This is a big problem in streaming data etc. It looks like this: 22:36 kernel: hub 4-0:1.0: state 5 ports 6 chg 0000 evt 0008 22:36 kernel: ehci_hcd 0000:00:10.3: GetStatus port 3 status 00180b POWER sig=j PEC \ CSC CONNECT 22:36 kernel: hub 4-0:1.0: port 3, status 0501, change 0003, 480 Mb/s 22:36 kernel: usb 4-3: USB disconnect, address 2 22:36 kernel: usb 4-3: usb_disable_device nuking all URBs 22:36 kernel: ehci_hcd 0000:00:10.3: shutdown urb ca6e53c0 pipe c0420280 ep4in-bulk 22:36 kernel: ehci_hcd 0000:00:10.3: shutdown urb ca6e5440 pipe c0420280 ep4in-bulk 22:36 kernel: ehci_hcd 0000:00:10.3: shutdown urb ce69ce20 pipe c0420280 ep4in-bulk 22:36 kernel: ehci_hcd 0000:00:10.3: shutdown urb c0417f60 pipe c0420280 ep4in-bulk .... All VIA motherboards with the IDE problem have the problem with the disconnects to (AFAIK). That's the story. It was startet by Rene Hermann on linux-devel without solution, when I came up with my usb-disconnect problem and we found the similarities about this. See the same thread on linux-usb-user http://marc.theaimsgroup.com/?t=113506436100003&r=1&w=2 and thread "External USB2 HDD affects speed hda" http://marc.theaimsgroup.com/?t=111749614000002&r=1&w=2 on linux-devel about this. So. The question is: How broken is the VIAchipset/driver/etc. How to solve this? What's the role of the usb-driver in this story. - E.g. Loading/Unloading ehci-hcd uhci-hcd affects ide-transferrates. - Making the CPU utilized !!!increases!!!! the IDE transfer rate. - Streaming data on ehci-hcd causes disconnects of devices after some time. Normal IDE transferrate : 36MB/s lircd with lirc_i2c and lirc_dev loaded : 14MB/s ehci-hcd loaded and once used : 22MB/s cpu 100% utilized : 55MB/s This is "just" doubling transfer rates with a snip. So whats going on here? It looks like DMA/BusMastering is taking place when CPU is utilized (Not realy knowing). But what happens when ehci-hcd, lircd are loaded which only use the usb-system? Any ideas? Helmut -- My GNUpg fingerprint http://www.gnupg.org 4563 F4FB 0B7E 8698 53CD 00E9 E319 35BD 6A91 1656 ------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Do you grep through log files for problems? Stop! Download the new AJAX search engine that makes searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! http://ads.osdn.com/?ad_id=7637&alloc_id=16865&op=click _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
