Antti Palosaari wrote: > Heinrich Langos wrote: >> Moikka Antti, >> >>> vp7045 does not have PID-filters. >>> I think difference comes from different USB-transfer settings. vp7045 >>> uses BULK packet size 4096 and af9015 uses BULK packet size 512 for >>> USB2.0 and BULK packet size 64 for USB1.1. Therefore af9015 sends 8 >>> times more packets than vp7045 (I guess). >>> >>> One thing more you can test - use USB1.1. To force USB1.1 remove USB2.0 >>> driver by rmmod ehci_hcd. After that plug af9015 stick and look from >>> logs it detects USB1.1 and uses PID-filters. af9015 driver now uses >>> smaller packet size for transfer that can change load (bigger?). > >> seems you are right. The transfer with PID filter in usb 1.1 causes >> about 30% load in contrast to 19% with usb 2.0 >> >> is there a way to increase the packet size for those bulk transfers? >> for usb 2.0? for 1.1? > > Actually AF9015 chip offers registers to configure packet size. But > those which are now used are default ones and rather many devices (other > than af9015) are using just same. That's why I am not sure if I want > change those to bigger ones. > > I will make test version that uses 4k packets for your tests. If it > resolves problem then we should consider for example adding module param > for setting desirable packet size. I will inform you when test version > is ready - It takes day or two. Unfortunately 512 seems to be biggest allowed packet size so I cannot increase it. Anyhow, there is other configurable parameter called packet count. I increased that from 348 to 512 but I doubt it does not have any effect. Feel free to test. If it does not change load then I think we cannot do more. Test tree: http://linuxtv.org/hg/~anttip/af9015_powertop/ regards Antti -- http://palosaari.fi/ _______________________________________________ vdr mailing list vdr@xxxxxxxxxxx http://www.linuxtv.org/cgi-bin/mailman/listinfo/vdr
