Dual Processor vs Dual Core info?

[Claudius-07]

I have done a bit of research on-line in regards to dual processors vs dual core (or more than 2 etc.), but it seems so much of the data dates back to 2006. I was tasked at work to look into upgrading our systems. We are currently running Intel P4 1.8 and also some other crap Intel P4 D systems.

We are a small unit... we mainly do SQL (query DB2 and oracle -- the servers are not an issue.. top of the line), some HTML... some other programming and the usual crap work stuff, email, Microsoft Office yada yada.

I have always noted it's mainly network resources and speed that has been our bottleneck since you get 10 guys hitting massive databases and if i am running 4 queries by myself at once hitting massive databases and I want to edit some HTML, have Outlook open, a few instances of IE, everything comes to a crawl. We all have 2 if not 3 computers at our stations and they all suck equally.

I need to explain the subtle differences to the brass about multi CPU vs multi core. I need a cole's notes approach. I personally told them all to simply get us regular Intel Quad cores... heck 9550's... whatever heck we might just need dual core Core2 etc. They wont touch AMD for stupid reasons so I can't suggest X6 etc.

They are talking about fiscal restraints but some of the ideas the IT department came with in regards to multi CPU systems made my eyeballs fall out. Thus they asked me what I thought and if we even remotely need these crazy multi CPU systems. I am not a 100% techie, but I understand that most of the work is done on the servers not at the local side... hence why I am trying to explain why we probably don't need the multi CPU systems.

Any suggestion as to a simple answer I can provide... ie.. we don't need multi CPU systems.. the difference if any over a multi core system for OUR needs is not warranted because....

thanks.

 

[Sp12]

On the Intel side of things the C2Q series is not a good choice in price/performance terms.

Multicore typically has slightly better performance/core/$ in that it's all on the same die (reduced latency), and is cheap/easy to implement (regular motherboards, no need for dual QPI Xeons). Dual socket means more expensive mobos/CPUs, but higher scalability per system (e.g., more power in one consolidated system, which can save money in eliminating redundant components like power supplies/cases that two separate multicore machines would have).

If this is truly for professional use a Xeon or Opteron may be worth looking into over a standard i5/i7, though I suspect your bottleneck may be at least in part due to IO.

 

[ModestGamer]

in todays world. there are many options. in the past you had some really bad design constraints that forced multi cpu systems. With the newer process blah blah blah the all on one die multicore cpu's almost always outperform 2 of the same cores on 2 seperate sockets. briefly when the dual cores where new the performance difference was marginal. newer generations however this is no longer the case.

as for the amd comments. if the code running on your systems was built with the Intel compiler you'd be better off with intel cpu's.

 

[BD231]

All you need to focus on are quad cores and plenty of ram, I wouldn't put so much faith in that database though, sounds like the server itself is the bottleneck.

 

[Ben90]

If a p4 @ 1.8 is performing the tasks you need at even 1/20th of the required pace, there is absolutely no need for a multi socket system. Sounds like your IT department doesn't really know what its doing.

 

[Vette73]

Yea I was gonna say AMD X6 with DDR3.

But if that is out then get a I5 quad.

 

[mindwreck]

if a 1.8ghz p4 is working for you. any modern multicore cpu would be worlds faster. the first p4s were poor cpus even during its time. the athlons were kicking intels butt at much slower clock speeds. even a dual core i3 530 that can be had for about 100 bucks is at least 4-6x faster than that old p4 and p4ds.

 

[degibson]

If you want to explain multi-socket vs. multi-core to non-technical brass, a good analogy is an office.
Mutli-core: many people working in one office.
Multi-socket: many people working in different offices.

The latter approach isn't going to work for all organizations -- communication between offices is lame in a lot of situations.

 

[Cogman]

If you want to explain multi-socket vs. multi-core to non-technical brass, a good analogy is an office.
Mutli-core: many people working in one office.
Multi-socket: many people working in different offices.

The latter approach isn't going to work for all organizations -- communication between offices is lame in a lot of situations.

Except they might get the mistaken notion that more offices = better. 4 cores on one die is better than 4 cores on 2 dies. I'm failing to come up with a good analogy, perhaps something like "Its like driving 2 cars to work with 4 people vs driving 1 car to work with 4 people. Both situations will get the job done, but one is quite a bit more efficient. Plus, all 4 can chat in the car easily while with 2 cars, car chat is not so natural."

It really doesn't sound like you need beefy systems. I would shoot for getting the low end I5 (Quad core for nice parallel compiling if needed). Getting a dual processor system would be a waste of money on anything less than a server.

 

[Ben90]

It does depend on the workload slightly. Multisocket systems have slightly more available cache per core due to less coherency (wow coherency is a word). However more cores on the same die usually achieves slightly better performance due to a coherent cache.

 

[Idontcare]

It does depend on the workload slightly. Multisocket systems have slightly more available cache per core due to less coherency (wow coherency is a word). However more cores on the same die usually achieves slightly better performance due to a coherent cache.

Not just cache coherency, but it also is impacted by thread migration since cache contents need to migrate with the thread.

Migrating threads across "remote" cores, be they within the socket but MCM'ed to a differing die or to a core on another socket, incurs a performance hit that is more substantial than that of migrating a thread and its associated cache contents to a core that is "local".

 

[Cerb]

What exactly comes to a crawl? Or, to say it another way, when IE and Outlook are waiting on whatever, can you still go open the start menu, browse your hard drive, start up included games, etc.?

If so, and it's just the network apps, while upgrades would be good, there could also be network issues to work out. A single hub, FI, can totally ruin a LAN . However, a little SQL and Outlook should not be killing the network, unless it's 10Mb, or has a really bad design.

Also, how much free RAM do you have on your desktop, when all this stuff is open? Especially the P4Ds, as they are likely to have more total. You may need more of that, more than anything else.

If AMD is out, for desktops that just work as clients, not doing any beefy workstation stuff, Core i3 w/ HT will leave what you've got in the dust. Make sure they all have 4GB of RAM, and you'll be good to go for several years, yet.

I'm thinking low RAM, P4s w/ SDR SDRAM (but that doesn't account for performance problems w/ the P4D systems), and/or bad network management, and/or the servers are not as top of the line as you think they are.



If you are absolutely doing an upgrade cycle, and the desktops are doing no heavy lifting, Core i3 systems, w/ 4GB RAM, and if you can get it, with DVI ouputs onboard (I don't know if you use big vendors or not, but if so, this should be very easy to come by), would do the trick. If the desktops are doing serious work, move up to at least the i5 760 (a real quad).

 

[Lorne]

The only real difference you will find between multi core to multi socket clock per clock is more bandwidth per core on multi socket, But the cost in equel ram and multi socket MB raises the price 2 fold and if it requires FB dimms 2x that.

Any C2D or C2Q clock per clock is 500% faster then any P4 system, The I or Core10 series is 2x that.

We just upgraded from a Dual P4 Xeon 1.8 HT 3 gigs DDR1800, To a single C2Q 2.6 dual channel DDR3 and its unreal the difference.

You can keep it cheap and simple and still be upgradable when prices drop with a C2Q or I3/I5, Only use a Xeon for the sever if must as its a waste of money for workstations.

Here is the best (In my opinion) latest aticle on multi core vs multi socket.
http://www.tomshardware.com/reviews/xeon-x5680-5600-series-westmere-ep,2692.html