Re: DMA transfers in 2.5.67

[mru@users.sourceforge.net (Måns Rullgård)]

Ivan Kokshaysky <ink@jurassic.park.msu.ru> writes:

> > I set the latency to 128 using setpci and now I get 66 MB/s.  Other
> > values give slower transfer rates.  Is there some other setting that
> > could improve it even more?
> 
> Interesting. Did you set latency 128 for all devices or only for
> 3Dlabs card?

Only the 3Dlabs.  The remaining cards are configured like this:

00:05.0 Ethernet controller: 3Com Corporation 3c905C-TX [Fast Etherlink] (rev 78)
	Subsystem: 3Com Corporation 3C905C-TX Fast Etherlink for PC Management NIC
	Flags: bus master, medium devsel, latency 64, IRQ 25

00:06.0 Display controller: 3DLabs GLINT R3 (rev 01)
	Subsystem: 3DLabs: Unknown device 0121
	Flags: bus master, 66Mhz, medium devsel, latency 128, IRQ 27

00:07.0 RAID bus controller: Triones Technologies, Inc.: Unknown device 0008 (rev 07)
	Subsystem: Triones Technologies, Inc.: Unknown device 0001
	Flags: bus master, 66Mhz, medium devsel, latency 120, IRQ 26

00:07.1 RAID bus controller: Triones Technologies, Inc.: Unknown device 0008 (rev 07)
	Subsystem: Triones Technologies, Inc.: Unknown device 0001
	Flags: bus master, 66Mhz, medium devsel, latency 120, IRQ 26

00:08.1 IDE interface: Contaq Microsystems 82c693 (prog-if 80 [Master])
	Flags: bus master, medium devsel, latency 0

00:08.2 IDE interface: Contaq Microsystems 82c693 (prog-if 00 [])
	Flags: bus master, medium devsel, latency 0

00:08.3 USB Controller: Contaq Microsystems 82c693 (prog-if 10 [OHCI])
	Flags: bus master, medium devsel, latency 0

00:09.0 USB Controller: NEC Corporation USB (rev 41) (prog-if 10 [OHCI])
	Subsystem: Adaptec: Unknown device 0035
	Flags: bus master, medium devsel, latency 64, IRQ 24

00:09.1 USB Controller: NEC Corporation USB (rev 41) (prog-if 10 [OHCI])
	Subsystem: Adaptec: Unknown device 0035
	Flags: bus master, medium devsel, latency 64, IRQ 28

00:09.2 USB Controller: NEC Corporation: Unknown device 00e0 (rev 02) (prog-if 20)
	Subsystem: Adaptec: Unknown device 00e0
	Flags: bus master, medium devsel, latency 68, IRQ 32

As you can see, the good IDE controller (Triones/Highpoint hpt374) has
a latency of 120.  Disk transfer rates are still only half of what I
get with a 2.4 kernel.  What could be the cause of this?


-- 
Måns Rullgård
mru@users.sf.net