Mem clock is both times 166MHz. I don't know whether are differences in cycle access and timing, but memclock is fine. Following Siarhei hints of initialize the buffers (around 1.2 MByte each) I get different results in 22kernel for use of malloc alone memcpy = 473.764, loop4 = 448.430, loop1 = 102.770, rand = 29.641 calloc alone memcpy = 405.947, loop4 = 361.550, loop1 = 95.441, rand = 21.853 malloc+memset: memcpy = 239.294, loop4 = 188.617, loop1 = 80.871, rand = 4.726 In 31kernel all 3 measures are about the same (unfortunatly low) level of malloc+memset in 22. First of all: What performance can be expected? Does 22 make failures if it is so much faster? Can the later kernels get a boost in memory handling? I used a standard memcpy (think this is glib and hence not neonbased)? To be neonbased I guess it has to be recompiled? How can I find out that neon and cache settings are ok? Using a Omap3530 on EVM board Unfortunatly I don't have a Lauterbach, just a Spectrum Digital which works only until Linux kernel is booting. Best regards Steffen -------- Original-Nachricht -------- > Datum: Wed, 14 Oct 2009 08:59:05 -0500 > Von: "Woodruff, Richard" <r-woodruff2@xxxxxx> > An: "epsi@xxxxxx" <epsi@xxxxxx>, "Premi, Sanjeev" <premi@xxxxxx>, "linux-omap@xxxxxxxxxxxxxxx" <linux-omap@xxxxxxxxxxxxxxx> > Betreff: RE: RE: Memory performance / Cache problem > > There is no newer u-boot from TI available. There is a SDK 02.01.03.11 > > but it contains the same uboot 2008.10 with the only addition of the > second > > generation of EVM boards with another network chip. > > > > So I checked the uboot from git, but this doesn't support Microns NAND > Flash > > anymore. It is just working with ONENAND. > > > > I found a patch which shows the L2 Cache status while kernel boot and > > implemented it : L2 Cache seems to be already enabled - so this is not > the > > reason. > > > > So any other ideas? > > Are you confident your memory bus isn't running at 1/2 speed? > > I recall there was a couple day window during wtbu kernel upgrades where > memory bus speed with pm was running 1/2 speed after kernel started up. > This was somewhat a side effect of constraints frame work and a regression in > forward porting. It seems unlikely psp kernel would have shipped with this > bug but its something to check. This would match your results. > > If your memcpy() is neon based then I might be worried about > l1neon-caching effects along with factors of (exlcusive-l1-l2-read-allocate cache + pld > not being effective on l1 only l2). > > Which memcpy test are you using? Something in lmbench or just one you > wrote. Generally results are a little hard to interpret with exclusive cache > behavior in 3430's r1px core. 3630's r3p2 core gives more traditional > results as exclusive feature has been removed by arm. > > If you have the ability using Lauterbach + per file will allow internal > space dump which will show all critical parameters during test. It's a 1 > minute check for someone who has done it before to ensure the few parameters > needed are in line. I can send an example off line of how to do capture. I > won't have time to expand on all relevant parameters. > > Regards, > Richard W. -- Neu: GMX DSL bis 50.000 kBit/s und 200,- Euro Startguthaben! http://portal.gmx.net/de/go/dsl02 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
