Topic: Why Dual Processors?

[Stephan Goeldi]

Why should one use dual processors with e-smith?
Is there any advance of speed?
Maybe SQL access?
Is there any Benchmark?

[try2break]

Why dual proc's on any system?  Speed.  Maybe they run cgi scripts and dole out lots of files with thier e-smith.  Everybody uses it differently.

[Stephan Goeldi]

Tell me the numbers!
I wanted to hear about the benchmarks of dual processor systems.
2 processors doesn't mean double speed.

[Karl]

Dual Processors ?
Why - because we can, no other reason. I picked up a Tyan dual proc M/B for about $70 US with on boad scsi,lan,etc. And also two P3-450's for $ 140 US.
We also will be running a 1000 line web shop soon so thought that it would be worth while. As I said at the start, " only because we can "

[Stephan Goeldi]

OK, I'll give up. Although I asked for comparisons or benchmarks on the "experienced user" forum for 3 times now I didn't receive any usable answer. It seems that I have to look on the redhat site for these answers. "Because we can" is no answer to my questions.

There once was an interesting discussion about the pros and contras of RAID-5 and why it isn't implemented in e-smith. I don't understand why there is not this kind of knowhow about dual processing.

In cases more RAM would be preferable. In other cases maybe a dual processor system. It depends on the targets. Databases, Caching, Email etc. Different needs. A customer with the need of a simple website will not need a dual processor system except his website depends on databases and content management systems (but I said "simple website").

I am heading over to the "experienced users" of plain Redhat now. Perhaps I will share my findings with the readers here, if anybody is interested

[Kees Blokland]

Think about it this way:

Unless you are feeding a gigabit-network, any old ( yes even a 233mhz) system will be able to saturate a network card..

So unless you are really building something for a massive application, I would guess almost anything will do for e-smith.

That, in my opinion is also the great strength of this product.
Of course nobody stops you using a 1.5 Gig processor, but what use is it when all it does is keep the house/office warm ?

Don't forget, in only a very few cases is the cpu('s) the bottleneck in the system
If anything, add as much memory as the motherboard will hold, and even the most humble system will spring to life. Don't forget, this is NOT windozs.

And yes, I've got an old dual pentium pro system (200Mhz)  because I got it dirt cheap. It's fun, but can I see the difference between this one and a 200Mhz single cpu on a 100 meg network ? not really.

Would I ever get a dual pentium system for any application ?
Not at the moment, if I needed massive power, I would use multiple boxes!

These remarks are not based on any science, just plain old observation.
I don't believe in the wintel numbers game, they mean little or nothing.

[Gerald Jansen]

I completly agree with Kees. Too much is made of cpu speed. My most used e-smith boxes have Cyrix 200 or 233MMX chips and motherboards that I got for nothing when upgrading client systems. in most cases 32 or 64MB of memory works just fine on a DSL connection. I use these systems to host low volume php portals and informational web sites. I have never had anyone complain about speed. From my view too many spend too much for capacity that is never used. If a server gets bogged down, add another one on the same DSL connection with a separate Static IP. Works great and costs virtually nothing.

[z00100]

I disagree with you 100%!!

CPU speed does matter, it all depends what you are doing.

I run a website that has quite and I mean quite active forums, they all use php/mySQL, and I also give out webmail for my users.

Since all the pages are dynamic, and mySQL is used extensively, the CPU utilization is quite high.

For example, on my Abit BP6 with dual Celeron 300A's running at 468 each, my CPU util is around 50% with about 450-550 users at any given time.

Sometimes my userbase peaks, and I need the oomph of another processor to help!!

Trust me, CPU speed, and dual processors are important!!

I can give you some benchmarks if you want, but you will have to wait till tomorrow, it's beddie bye time for me right now!

[Kees Blokland]

Yes indeed, it al depends on what you are doing.
In your case with that load I can imagine it makes a difference, but the question is, would you go and buy a dual pentium board, or use 2 systems ?

I would still go for two cheapies, more reliable etc..

Also, if you are using 2 celerons, with 500 users each, then you prove that you can run 250 users on a misery celeron. (Celeron's are not that great any more, never were in the first place..)
Now If you would use a cpu with a bit more cache mem and a lot more memory!!
your'e back to what I said. Anything will do even with a large customer load!

( Celerons etc, anything below 500Mhz in many companies books is 'outdated' equipment. Not in mine though!, hence the statement, use anything you can get your hands on, and it will do fine!)

>For example, on my Abit BP6 with dual Celeron 300A's running at 468 each, my >CPU util is around 50% with about 450-550 users at any given time.

kees

[Kees Blokland]

Another thought,

I have to come up with some good reasons for using an e-smith setup..

Your statement proves once again, that you can run a lot of users on a simple box.
This 'simple' is what wintel people tell customers, not me..!

Can you tell me your url?

kees

[Stephan Goeldi]

> Yes indeed, it al depends on what you are doing.
> In your case with that load I can imagine it makes a
> difference, but the question is, would you go and buy a dual
> pentium board, or use 2 systems ?

Yes, why not? Here in Switzerland the difference between a 1-cpu-mb and a dual-cpu-mb is about $60. Then a second 1.2GHz AMD cpu for about $285 and you're done. A second box wouldn't be cheaper.

> Now If you would use a cpu with a bit more cache mem and a
> lot more memory!!
> your'e back to what I said. Anything will do even with a
> large customer load!

2 IBM SCSI Harddisk at 4,5ms average
1,5GB RAM (PC133)
2 x 1.2GHz AMD K7

There is a database driven Content Management System which needs a fast cpu response. Apache with multiple virtual hosts rewriting to the Content Management System (Zope). It is possible that the customer wants the Oracle database installed. I think this one sucks a lot of resources, doesn't it? So this configuration would be ok, doesn't it? Of course, I could offer a system which is about $2000 cheaper, but does it really matter if speed is important?

[z00100]

Kees Blokland wrote:
>
>
> Yes indeed, it al depends on what you are doing.
> In your case with that load I can imagine it makes a
> difference, but the question is, would you go and buy a dual
> pentium board, or use 2 systems ?
>

Well, it depends.  Ultimately it is better to run 2 seperate systems, each optimized for it's task, but then again, if there is a lot of network traffic between the two systems, then once again, it becomes a bottleneck.

But if you are running a single machine webserver then a duallie is a good go, but if you are running an enterprise website, then redundancy is key, and several systems is a better bet than putting all your trust on just 1 system!

> I would still go for two cheapies, more reliable etc..
>
> Also, if you are using 2 celerons, with 500 users each, then
> you prove that you can run 250 users on a misery celeron.
> (Celeron's are not that great any more, never were in the
> first place..)

The only caveat of the Celeron is the fact that it has very little cache, that makes it inefficient for heavy duty server work, however, since it's cache runs at full processor speed, it can be handy for certain apps.  So it all depends, on what your requirements are.

Also, don't forget that a single P-100 can handle thousands of users ONLY if the pages are static HTML and there is a ton of RAM on the system.  The minute you add dynamic pages, or mySQL or other fancy tricks, then you are screwed.

> Now If you would use a cpu with a bit more cache mem and a
> lot more memory!!
> your'e back to what I said. Anything will do even with a
> large customer load!
>

My current server has 256MB of PC-133 SDRAM and that is more than enough for my needs right now.  

> ( Celerons etc, anything below 500Mhz in many companies books
> is 'outdated' equipment. Not in mine though!, hence the
> statement, use anything you can get your hands on, and it
> will do fine!)
>
> >For example, on my Abit BP6 with dual Celeron 300A's running
> at 468 each, my >CPU util is around 50% with about 450-550
> users at any given time.
>
> kees


Also, perhaps you didn't notice, but I said my 300A celerons runnuing at about 500 Mhz, that means I am running them at 100 Mhz FSB instead of 66Mhz, so just right there it performs just as well as a P2 500 but with 1/4 the cache.

So technically speaking I have a Dual P2 500 with 128K cache each.

[z00100]

I should let you guys know that for a server the L2 Cache is VERY VERY VERY important.

Let me give you an example......

My Dual Celeron 468 performs just about the same as a Slot A Athlon 550 with 512K cache.

So that means a 936Mhz Celeron with 256K cache will perform about the same speed as a 550 Athlon with 512K cache.

Why do you think Xeon's are so expensive??  Their CORE is identical to a P2/P3, but they have 1 or 2 megs of cache and that makes them REAL fast for server usage.

[Greg]

My two cents-
I've run all kinds of Apache/MySQL configurations on all kinds of cheap/old hardware. The best thing I ever did was put MySQL on a backend server, seperate from Apache. Even on a P133 with 128mb of ram, the php sites performed better than when on a dual PII 450 along side Apache.