Date: Sat, 16 Oct 2010 19:29:37 +0000 (UTC) From: Alexander Motin <mav@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r213931 - head/sys/dev/usb/storage Message-ID: <201010161929.o9GJTbqW087289@svn.freebsd.org>
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Author: mav Date: Sat Oct 16 19:29:37 2010 New Revision: 213931 URL: http://svn.freebsd.org/changeset/base/213931 Log: Allow umass to use bigger transactions for USB 3.0 devices. It is less important for USB 2.0 devices and some of them reported to have problems with large transactions. But USB 3.0 benchmarks show that limited number of transactions per second on USB makes impossible to reach high transfer speeds without using bigger transactions. On my tests this change allows to read up to 220MB/s from USB-attached SSD (at block size of 256-512KB), comparing to only 113MB/s without it. Reviewed by: hselasky Modified: head/sys/dev/usb/storage/umass.c Modified: head/sys/dev/usb/storage/umass.c ============================================================================== --- head/sys/dev/usb/storage/umass.c Sat Oct 16 19:25:27 2010 (r213930) +++ head/sys/dev/usb/storage/umass.c Sat Oct 16 19:29:37 2010 (r213931) @@ -2418,6 +2418,7 @@ umass_cam_action(struct cam_sim *sim, un case USB_SPEED_SUPER: cpi->base_transfer_speed = UMASS_SUPER_TRANSFER_SPEED; + cpi->maxio = MAXPHYS; break; case USB_SPEED_HIGH: cpi->base_transfer_speed =
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