Messages in this thread |  | | From | Jesse Wyant <> | Subject | Re: P4 Xeon summary inquiry | Date | Tue, 7 May 2002 00:12:28 -0700 (PDT) |
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I just put together a SuperMicro P4DCE+ (Intel i860/ICH2/CS4299 AC'97 codec [use the OSS i810_audio or ALSA's intel_8x0 or whatever it is]) with 1GB of Samsung RDRAM and two 2.0GHz Xeon (Prestonias.) Currently 2.4.19-pre7 with Ingo's interrupt patch, and timer balancing patch. Running on ext3, using RedHat 7.2.
I also tried the acpismp=force option to get into hyperthreading (successfully--it appears as though I have 4 CPUs), and the overall system seems just as fast as with the HT disabled. Qualitatively: kernel compile with HT disabled, using
'make -j2 bzImage; make -j2 modules; make modules_install; sync'
results in compile times around 3 minutes 45 seconds or so. With HT enabled, and using -j4 instead of -j2, my compile time comes down to around 2:57 or so--a significant improvement.
However, 'dnetc's throughput in RC5 keys/s is much lower with HT enabled: it runs 4 clients, and each client chugs through about 720kKeys/s. With HT disabled, the two dnetc clients run through 2.8MKeys/s each. (So it's around half as fast with HT enabled!) When I'm finished downloading RedHat 7.3, I'll reboot into Hyperthreading-enabled mode, and run 'dnetc --benchmark' to confirm this.
Haven't had a chance to benchmark more than that yet. But no gross issues when running with HT enabled. (Tribes2, Q3A and RTCW feel equally fast between the two configurations.)
-jesse
> I am trying to make a dual P4-Xeon box (P4DCE, Intel 869) work optimally. > After some search in list archives, I have found this points: > > - You need ACPI, and boot with acpismp=force, to have hyperthreading > (see 4 cpus) > - To balance interrupts, a patch from Ingo is needed > - To balance timers, one other patch was needed, but this in included > in 2.4.19-pre8 (do not know since which pre is there) > > I tried to boot with acpismp=force, but then performance was dog slow, > I could count lines scrolling on a rxvt. > I checked mtrr and look like working. Box has 1Gb of ram, so kernel > is using CONFIG_HIGHMEM4G=y. > Kernel is the standard highmem Mandrake kernel in 8.2 > (2.4.18-6mdkenterprise) that is mainly a plain 2.4.18 with some > .19-pre1 fixes. > > Any correction ? Any known problem in 2.4.18 about this issue that > has bee corrected in pres for 19 ? > > Any idea about the performance loss ? > - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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