Testing single core / processor in Java

Hi all,
I delevoped multi-threaded application and I would like to test it on:
- machine with 2-cored processor
- machine with 2 processors
Is there possibility to push JVM to use only one core / one processor of hosting machine ? Just for comparision of efficiency ?
Regards,
Maciej

There isn't anything in the API for this. Probably the best thing is to disable or take all but one CPU offline and then run the java application. One way to do this on Windows is to add the /NUMPROC switch to boot.ini (not sure if you can do this dynamically). On Solaris the prsadm command can be used to take CPUs offline. There are probably many ways on Linux - one way is the maxcpus paramter to the kernel line in grub.conf. Hope this helps.

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CS4 and single core processors

Hi,
I have a Mac Mini with a 1.5 GHz Intel single core processor and i want to buy Creative Suite 4 Web Standard to use on it.
But when i read the requirements for CS4 it mentions that a Mac should have the following:
PowerPC G4 or G5 or multicore Intel processor
Does CS4 work OK on a Intel single core processor?
Is a multicore processor specified because a small number of features benefit from it?
Any advice would be appreciated.

I used InDesign CS4 for a while on a 1 Gig 800MHz G4 tiBook. It was reasonably satisfactory given that I knew I was working in an underpowered setup -- I've since replaced the tiBook with a MacBook Pro with 4 Gigs.
I think that if you stick to your "one app at a time" philosophy, you'll be happy enough with the Mac Mini. I think Adobe was just reducing the testing and support load it had to deal with by apparently excluding older processors.
Dave

Removing single core processor

Hi,
I just recently bought an early 2006 Mac Mini. I've ordered a newer duo core processor and additional ram. Looking at the processor, I'm not sure how to remove it. There's no lever or locking mechinism that I can see. Any help would be appreciated. Here's the pic:

Based on your photos your model is not upgradeable. This is the upgradable one.
https://www.ifixit.com/Guide/Mac+mini+Model+A1176+Core+2+Duo+Processor+Replaceme nt/1178

Processor question - Dual core vs. single core.

I currently have an Aspire 6930 laptop that I bought about a year ago on clearance from Best Buy. I'm quite happy with it. It has an Intel Core 2 Duo processor (2.0 GHZ, 800MHz, FSB, 2 MB L2 cache), 3 GB DDR2, 320 GB HDD if that means anything. I'm not a computer geek so really don't know much about this stuff.
Our old laptop is a modular laptop (about 4 years old) which my husband is using (I won't let him mess with my Aspire - long story) and it's pretty much falling apart. None of the USB ports work, the CD/DVD RW is broken, one of the hinges is busted so it won't close properly and it runs slower than a snails pace as he's dowloaded any and all "speed up your PC" and "diagnose your PC" programs from the web - if it's on the web it must be true, right???? Anyway, I've taken pity on him and have decided to try to buy him a new laptop as a combination 10 year anniversary/42nd birthday/Christmas present. Money is a HUGE issue as I'm a SAHM and have been pinching pennies and clipping coupons from the grocery money to try to come up with some funds for this surprise. I'd like to stay around $400.
I've found this one at Best Buy and it has good reviews.... http://www.bestbuy.com/site/Acer+-+Aspire+Laptop+with+AMD+Athlon%26%23153%3B+Single-Core+Processor/9...
But it says it has a single core processor. What exactly is the difference with single core vs. duo core???
We are not gamers. DH basically uses the computer to surf the web, watch Youtube video's, upload and download photo's, burn DVD's, etc. He does talk with family overseas so I would need/like to add a webcam.
I was also looking at this Asus model... http://www.bestbuy.com/site/Asus+-+Laptop+with+Intel%26%23174%3B+Pentium%26%23174%3B+Processor+-+Mid...
But the Asus has a Pentium processor which I've heard isn't the best???? Also, it's over $150 more. Is the duo processor and increase processor speed (1.6GHz vs 2.1 GHz) really going to increase the speed/response time significantly for what we do on the computer?? An extra $150 is going to be really tough for me to come up with but if it will truly make a significant difference I will try to find it somewhere.
Your thoughts/recommendations would be appreciated.
hugs -
lisa

Thanks for the input. We really don't have the space for a desktop which is why the laptop worked so well for us. The only place to put a desktop is on the kitchen table and then we are always taking it apart when family come for dinner (which is often). I thought of netbook, but it does seem so limited. My husband is an amateur photographer and I would like the larger screen so that if he decides to persue this he would be able to do some basic photo editing, etc.
I think I will go with the dual core processer. BB has an HP that is $429
http://www.bestbuy.com/site/HP+-+Laptop+with+Intel%26%23174%3B+Pentium%26%23174%3B+Processor+-+Black...
and then another HP that is $499
http://www.bestbuy.com/site/HP+-+Laptop+with+Intel%26%23174%3B+Pentium%26%23174%3B+Processor+-+Piano...
and I can't seem to find the difference?????? Except the cheaper on has more RAM??? Doesn't seem to make sense.
Thoughts on the HP???
hugs -
lisa

HP 4510S laptop. has dual core processor but is only running one half of it.

This system is running on Win 7 32bit. If I upgraded to W7-64 bit would the system then use both halves of the processor?

I use BELARC advisor which lists all hardware, SW on my system. It also tells me what processors I have, memory, etc. It will also tell me if I have a dual or single core processor and whether it is running both cores or only one. My gateway NV50 is running Win 7-64 bit and BELARC tells me how it is working on both cores. But my wifes LT which is an HP has win 7-32 bit for an OS and Belarc advises that it is only running one core. That is why I asked the question. I am upgrading the HD from 250 to 750 gb and maxing out her memory. Maybe then she will quit complaining about how slow it works.

Multi-core processor

How do you take advantage of a multi-core processor in Java.

cotton.m wrote:
Try buying it dinner? Always remember though, no means no.What's the difference between a lady and a diplomat?
When a diplomat says yes, he means maybe. When he says maybe, he means no. And if he were to say no, he wouldn't be a diplomat.
When a lady says no, she means maybe. When she says maybe, she means yes. And, if she were to say yes, she wouldn't be a lady.

Will Illustrator run on 1.8GHz quad core processor?

I am reading that Illustrator CS4 requires a 2.0GHz processor to run. I am assuming that is for a single core processor. I am considering buying a new computer running Vista 64 bit with a1.8GHz quad core processor and 4GB of RAM. Would Illustrator CS4 run ok on such a system?
Thanks,
Bob

I think 1400 by 900 is good since you can run many of the motion graphic programs on such a monitor.
1920 x 1200 is very good but now things have gotten to the point that they have higher resolution available.
So I recommend the highest you need. The reason i say this is that once applications are made multi core worthy and go 64 bit it requires more resources but it will perform better and what I mean by better is not necessarily speed on any one task but the it will offer functions that are not possible on the current cpus with the current application.
It just seems to me you need a little more then what you are getting, a little more so that in the very near future you will not have to upgrade again causing you to end up paying even more that you thought you were saving.
If you understand my logic.
Though the answer to your original question is it can probably run, how well you would probably have to tell us after you get it.

What Do Multi-Core Processors Do?

I posted a thread on this some time ago, and my understanding was that a multi-core processor allowed for computing tasks be performed simultaneously. Rather than one after another, which is what a single-core processor would do. This is often applied within the applications themselves, to increase execution speed. Such applications being multi-threaded applications.
But I've recently learnt that even single core processors can execute code in more than one thread. So in this sense, what extra functionality does having multiple cores give you? Or am I wrong in thinking that single core processors can do this too? I'm trying to weigh up the advantages of buying a Mac Pro over a different model like an iMac.
There's a hole in my understanding somewhere, I just don't know where it is.
Any info appreciated.
Many thanks,
Adam

multi-threading varies by application
Think of the system having reserved rights to 0, some background task(s) to 1, Safari on 2, etc. is one scenerio.
Some but not all or even a lot of apps are truly multi-thread.
Faster processor cores are still more important than how many cores.
one core with hyper-threading can execute two threads, and deliver 20-35% more in performance at the expense of running hotter and using more watts. HT came back in 2009 with Nehalem and Core i-Series.
Dual processor, two cpus, have been around for a long time on Macs back to G4/500DP and dual and quad-core is just more efficient to manufacture and build into systems (dual core Atom or A8's in mobile devices).
Programs that worked without HT sometimes don't work properly with H-T until they are recompiled and optimized properly.
Your real question is what Mac to buy though, and what you actually plan to run and do.
And there are processors for laptops, desktop, towers and more. And all have different performance.
http://www.intel.com/products/desktop/processors/index.htm
http://macperformanceguide.com/index_topics.html
Some iMac vs Mac Pro
http://www.barefeats.com/imac10o.html
http://www.barefeats.com/imac10v.html
So getting things to work in multi-core, multi-threaded, how much memory you want, the need for multiple drives (SSD boot drive and 1TB data drive even in iMac now), and graphic offerings.
Start with what you use, then to what you need to buy. Don't put the cart before the horse. A Mac Pro or iMac may seem at first to be on somewhat equal footing.
http://www.barefeats.com/wst10c2.html
There is a huge range in performance on MacBook/Air/Pro platform.
http://www.barefeats.com/mbpp31.html

Public static Thread currentThread() and multi core processors??

Hello,
I have the following basic question: what does public static Thread currentThread() mean in the context of multi core processors where several threads may execute concurrently?
Any clue welcome,
J.

Hi balteo,
When you invoke Thread.currentThread(), you get the reference of the current thread : the thread where you make the call.
Just try :
System.out.println("My program is running thread : " + Thread.currentThread().getName());
mean in the context of multi core processors where several threads may execute concurrently?Several threads may run concurrently with single core processors. The number of concurrent threads you may execute depends of the processors architecture and the OS.

Power Mac MDD G4 1.25 Single Core vs. Dual Core

I am purchasing a 1.25 MDD G4 that has the single core processor. I am going to be using it for music recording and creation.
Am I going to wish I had the dual core? Or will I not notice the difference? I was previously using a 700mhz imac with 765mb of ram and overloaded it pretty quickly.
This machine, with 1 (which is has) or 2 (which I might install) gigs of ram should outshine that pretty significantly even with a single core shouldn't it?

Dual if you can, especially if you're looking to go to Leopard during the life of the machine. Single G4 CPU and Leopard is painfully slow, even at 1.67GHz.
Even the current entry level iMac blows away most of the G5's, except maybe the quad cores) so G5's should be reasonably priced.

What the heck is Single Core, Dual Core, and Quad Core Processor Configurat

I am listing an eMac computer on ebay. I have all the information necessary except processor configuration. Do eMacs come with Single, Dual, or Quad processor configurations? Or does it vary? I don't even know what those are really.

Make sure to follow these steps when selling*:
http://www.macmaps.com/selling.html
As was already indicated all eMacs were single core.
Apple didn't start releasing multicore machines until the later G5s.
- * Links to my pages may give me compensation.

Jdeveloper dual core processor performance problem

I have a dual core 2.4 ghz processor and 2 gig of ram and Im running Jdevloper 9.0.5.2 and my performace is terrible. Other developers in the company have non-dual core processors and they can start up in debug mode using the Jdeveloper embedded oc4j our application in 10 seconds where it takes me 4 min!!!!! It is a struts,ejb web application. Is there anything I can do to help in debug mode??? cheers.
Murray

Hi Bernard,
Which version of McAfee are you using?
On my (personal) laptop, I'm using McAfee VirusScan 9.0.10. I don't frequently run JDeveloper on this laptop, but when I do, it's not experiencing signficant startup delays (it's a very low power machine: PIII 650 512Mb)
McAfee VirusScan seems to have very few configuration options (noticably different from Norton, which I use on my corporate desktop machine). I specifically remember changing the "File Types to Scan" option to "Program files and documents only". You can get to this by right clicking the "M" notification area icon, VirusScan->Options menu, Advanced button on the ActiveShield page.
In Norton, I think I have it configured so that it only scans files on write rather than on read. I also exclude directories which contain jdeveloper installs or other large Java apps (although scanning only on write elliminates most of the performance problems anyway and still leaves your system reasonably secure).
The easiest way to convince your MIS dept that the virus checker is the source of your problems might be if you ask them to allow you to turn it off in order to test the difference it makes to performance. It's a reasonable request to make if you're trying to elliminate possible causes for the slowdown (from the description you gave, it does sound like the AV upgrade is the first place I'd start looking).
If the virus checker is the source of your problems, you'll probably be seeing massive slowness in most large Java applications that have a large number of JARs on their classpath.
Thanks,
Brian

What are the speeds of singe/multi core processor for iPhone 6

i have an iPhone 6 and have just run Geekbench 3 test for the processors and got:
SIngle Core 1164
Multi Core 2049
Geekbench give an average score of:
Single Core 1607
Multi Core 2831
The scores for my phone seem to be quite low in comparison to Geekbench results.
I this something I should be concerned with?

No, you don't have to be concerned. Every bench test will give you different results, and In the end it's a phone and not a high-end computer like the Mac Pro to do your video editing.

Compressor performance - single core transcoding?

I have a relatively new MacBook Pro (15" Retina, 2.6 GHZ i7, 1TB SSD, 16GB RAM). I am an experienced user of the Adobe Suite of products especially Premier Pro and Media Encoder. I have download Compressor and run a number of transcoding tests and found that trancoding takes considerably longer compared to Media Encoder. The Activity Monitor reports what looks like on a single core is running (e.g. 100% CPU and the graph showing only about 10% CPU utilization.
Is this right? Are there any settings that can be tweaked to get all the cores on this processor churning on the transcode?

Compressor is multi-core aware. It may be that your encoding job won't benefit from more than one core. I could be you're encoding a variation of H.264 that doesn't allow job segmenting.
Also, check your preferences, the Advanced section, how many "instances" is it set to? The max number is not always the most efficient. Do a test encode with the Max number, then decrease by one on following tests, see where the sweet spot is.
Finally, only single-pass H.264 will take advantage of the hardware encoding, not multi-pass.

Can Logic 8 take advantage of the Xenon 8-core processors?

I'm considering refreshing my entire studio now that Logic 8 is out (hardware and all). Does anyone know if the program can take advatange of the new Xenon 8-core processors? I have heard that the difference between 8-core and 4-core is not noticable unless the software can take advantage of all 8 of the processors. It's a big price difference between the two and I don't want to spend the extra money unless there is clearly a performance advantage to the 8-core.

I can attest that I'm seeing excellent performance with Logic 8 on the current generation of 8 core. I'm not sure if anyone has proposed a 'standard' reverb count test ala the Pro Tools D-Verb test but just to give you an idea:
My previous computer was a G4 single 733 with an upgrade card that made it dual 1.8 GHz G4. 1.25 gig of ram. On that system I could run 1 realtime Space Designer in Logic 7 as along with quite a few other plug-ins, but definitely only 1 Space Designer.
On my current 8 core setup, at 44.1KHz, 64 samples buffer size I ran 60 stereo Space Designers (4 inserts apiece across 15 tracks) and each core was running about 66% (2/3). I got tired of inserting reverbs at that point but I think it's a good indication of the efficiency and processing headroom available with this setup. All graphics are fairly snappy as well.
I took the plunge into 8-core land early because there were a couple of projects that I just had to take and my poor G4 absolutely couldn't handle it anymore. While the next gen of processors may well give you even more punch, I feel this level of processing ability will certainly be enough to handle the current demands of my music projects for at least a couple of years:)

Testing single core / processor in Java

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