usb 3.0 half speed with pci=nomsi
Hi,I have two similar linux machines with legacy PCI / USB 3.0 cards plugged in. These use the NEC uPD720200 USB 3.0 Host Controller and the xhci module.
System A "Fast": **************** USB 3.0 read performance of about 80 MB/s doesn't need pci=nomsi to see the USB 3.0 devices Snips of lspci -vv : --------------------Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx+
Interrupt: pin A routed to IRQ 21 Region 0: Memory at febfe000 (64-bit, non-prefetchable) [size=8K] Capabilities:  MSI-X: Enable+ Count=8 Masked- Capabilities: [a0] Express (v2) Endpoint, MSI 00 DevSta: CorrErr+ UncorrErr- FatalErr- UnsuppReq+ AuxPwr- TransPend- Capabilities:  #1033 System B "Slow": **************** USB 3.0 read performance of about 40 MB/s needs pci=nomsi to see the USB 3.0 devices Snips of lspci -vv : --------------------Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
Interrupt: pin A routed to IRQ 17 Region 0: Memory at fb000000 (64-bit, non-prefetchable) [size=8K] Capabilities:  MSI-X: Enable- Count=8 Masked- Capabilities: [a0] Express (v2) Endpoint, MSI 00 DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AIs it likely that the kernel option is what's dropping the USB 3.0 performance to about 1/2 speed?
If there is a suggestion to up the speed please let me know. --- John -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
[Older Fedora Users] [Fedora Announce] [Fedora Package Announce] [EPEL Announce] [Fedora News] [Fedora Cloud] [Fedora Advisory Board] [Fedora Education] [Fedora Security] [Fedora Scitech] [Fedora Robotics] [Fedora Maintainers] [Fedora Infrastructure] [Fedora Websites] [Anaconda Devel] [Fedora Devel Java] [Fedora Legacy] [Fedora Desktop] [Fedora Fonts] [ATA RAID] [Fedora Marketing] [Fedora Management Tools] [Fedora Mentors] [SSH] [Find Someone Special] [Fedora Package Review] [Fedora R Devel] [Fedora PHP Devel] [Kickstart] [Fedora Music] [Fedora Packaging] [Centos] [Fedora SELinux] [Fedora Legal] [Fedora Kernel] [Fedora QA] [Fedora Triage] [Fedora OCaml] [Coolkey] [Virtualization Tools] [ET Management Tools] [Yum Users] [Tux] [Yosemite News] [Yosemite Photos] [Linux Apps] [Maemo Users] [Gnome Users] [KDE Users] [Fedora Tools] [Fedora Art] [Fedora Docs] [Maemo Users] [Asterisk PBX] [Fedora Sparc] [Fedora Universal Network Connector] [Libvirt Users] [Fedora ARM]