Amd Vs P4 Ht

Emanon

I have read that HL servers and particularly NS servers run better on AMD than a P4 with HT. This is because NS uses a large amout of cpu and the fact that with HT you basicly split the cpu in half.(acts like a duel cpu system) My question to you is, Is this true?

For comparison sakes:

2.8 P4 HT
2800+ AMD (barton core)

billcat

Anytime you run a cpu in HT mode it pretty much cuts the amt of CPU power that a single process can actually use in half. The goal here is to allow a single process to run away with half of the CPU and still have part of the CPU be responsive to other processes. Much the same way a dual proc mobo/cpu combo would work. So yes, I could see how an amd chip would run faster than an intel HT proc. Try running that intel proc in non HT and see if you get better comparisons.

You should be able to set HT mode via bios and then you can enable/disable HT processing in the linux kernel. Not sure how wintel handles it. I turned off HT processing on my linux box and the OS uses the entire processor as one.

Here is the procinfo on my 2.8 HT:
more /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 15
model : 3
model name : Intel® Pentium® 4 CPU 2.80GHz
stepping : 3
cpu MHz : 2813.571
cache size : 1024 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 3
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov
pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe pni monitor ds_cpl c
id
bogomips : 5609.88


Notice that only cpu 0 list listed. So the OS only sees a single CPU even tho down in the flags you can see that the HT flag is there, indicating that the chip could run HT if I turned that on when I rebuilt the kernel.

Edit: Sorry to post linux stuff in the wintel forums, I'd just clicked on the last edited topic off the main forum page without noticing this was win32 space. In any case you should be able to enable/disable HT capabilities via BIOS and have the OS just see one large CPU rather than the virtual 2 that HT provides.

Emanon

Yep its official with a 2.8 or 3.0 P4 with HT enabled you cant support more than 16 players because your actually running a 1.4ghz NS server. CPU usage will not go above 50% because steam doesnt support the multiple processors.

I checked this by putting 30 public slots on a CO server and everyone was complaining of lag even though pings were not sky rocketing the feel of play sure did seem like it. Once back down to 16 slots, shots registered like a charm.

16slots full load rcon reports 86%cpu (No noticeable lag)
30slots full load rcon reports 86%cpu (Lab baby)

I wish I could test this with HT disabled but I dont have physical access to the box to change the bios.

Thanks for the INFO.

PS. I really wish steam would support HT or multiple processors.

modie

Ask whomever has your server to change it in the bios or hook up a kvm to the server so you can do it.

If your not running anything else on the server, it's well worth the effort to do it.