Date: Fri, 17 Mar 2006 22:02:31 -0800 (PST) From: "Jeremy C. Reed" <reed@reedmedia.net> To: Steve Kargl <sgk@troutmask.apl.washington.edu> Cc: freebsd-amd64@freebsd.org Subject: Re: amd64 webpage, 12GB memory? 64-bit or not? SMP or not? Message-ID: <Pine.NEB.4.62.0603172125420.10693@pilchuck.reedmedia.net> In-Reply-To: <20060318044110.GA8986@troutmask.apl.washington.edu> References: <Pine.NEB.4.62.0603171958350.10693@pilchuck.reedmedia.net> <20060318044110.GA8986@troutmask.apl.washington.edu>
index | next in thread | previous in thread | raw e-mail
On Fri, 17 Mar 2006, Steve Kargl wrote: > > How can I tell if a 2.80Ghz Xeon is a 32-bit Xeon or a 64-bit Xeon? What > > do I look for in the 6.0-RELEASE GENERIC i386 dmesg output? I do see: > > > > ACPI APIC Table: <PTLTD APIC > > > Timecounter "i8254" frequency 1193182 Hz quality 0 > > CPU: Intel(R) Xeon(TM) CPU 2.80GHz (2793.01-MHz 686-class CPU) > ^^^^^^^^^^^^^ > You're running a i386 kernel, which is 32-bit. I already know what it is currently running. In my email, I tried to indicate that it is running 6.0-RELEASE GENERIC i386 (twice in the parts you included in your reply). I am unclear if you are answering my question: How can I tell if a 2.80Ghz Xeon is a 32-bit Xeon or a 64-bit Xeon? > > Features=0xbfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,C > > MOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE> > > Features2=0x641d<SSE3,RSVD2,MON,DS_CPL,CNTX-ID,CX16,<b14>> > > AMD Features=0x20100000<NX,LM> > > Hyperthreading: 2 logical CPUs > > real memory = 3489071104 (3327 MB) > > avail memory = 3414630400 (3256 MB) > > > > How can I tell if it can take advantage of "options SMP" (from looking at > > 6.0-RELEASE i386 GENERIC output)? (I do see "Hyperthreading: 2 logical > > CPUs".) > > You're using a GENERIC kernel. IIRC, "options SMP" isn't included > in GENERIC, so you're running a UP kernel. You need to rebuild > the kernel I understand. I know it is running GENERIC as I mentioned. My question is: How can I tell if it can take advantage of "options SMP" (from looking at 6.0-RELEASE i386 GENERIC output)? > > I was told it has 12 GB of memory. The Hardware Notes also says "The > > largest tested memory configuration to date is 8GB." But I only see "real > > memory = 3489071104 (3327 MB)". > > The i386 is limited to 4 GB address space without options PAE. You > need to rebuild your kernel. Only i386 supports "options PAE". How can I tell if this system can support an amd64 (without physical access)? I am still unsure. Sorry if I misunderstood your reply. I know I am currently running a 6.0-RELEASE i386 GENERIC kernel. (And I know SMP is not in GENERIC). I want to know how I can find out if I should be running an amd64 kernel instead. I was under the impression that some (all?) 64 bit Athlons, Opterons, Xeons can also run the 32-bit i386 kernel. (I was sure I have seen this too.) I have been looking at src/sys/i386/i386/identcpu.c. But I am not sure how an 64-bit Intel Xeon would behave. (I am guessing it would be CPUCLASS_686.) I do see that my dmesg output has AMD featuress with "LM" which means 64-bit long mode. But I don't know if that means this is a 64-bit system. I see the dmesg says "Id = 0xf43" (this is the cpu_id). Doing some google searches show one "K8-class" and several "686-class" CPUs. Also NYCBUG's dmesg database has that same "K8-class" "Id = 0xf43" system. A "K8-class" is definitely from an amd64 kernel (as it is printed from the src/sys/amd64/amd64/identcpu.c). I am hoping the system I am looking at can run the amd64 kernel. Thanks for your reply. You got me searching into the kernel source now. Jeremy C. Reed echo '9,J8HD,fDGG8B@?:536FC5=8@I;C5?@H5B0D@5GBIELD54DL>@8L?:5GDEJ8LDG1' |\ sed ss,s50EBsg | tr 0-M 'p.wBt SgiIlxmLhan:o,erDsduv/cyP'home | help
Want to link to this message? Use this
URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.NEB.4.62.0603172125420.10693>