Memory

Has anyone tested how much memory past 4GB helps the speed of L4? I am running L4 on a system with 4GB and even with several programs running I am not even using half of my memory? I am just wondering if the extra expense of say 6GB or 8GB would be worth it.

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Bohuslav Wojnar

Has anyone tested how much memory past 4GB helps the speed of L4? I am running L4 on a system with 4GB and even with several programs running I am not even using half of my memory? I am just wondering if the extra expense of say 6GB or 8GB would be worth it.

Is your system running Windows OS 32 or 64 bit? If 32 bit, than (if I am not mistaken) your system can use only 3GB of the memory.

Rich DeRuiter

Has anyone tested how much memory past 4GB helps the speed of L4? I am running L4 on a system with 4GB and even with several programs running I am not even using half of my memory? I am just wondering if the extra expense of say 6GB or 8GB would be worth it.

Memory past 3.2GB is not accessible by a 32bit operating system.

But if you have a 64bit operating system, the more RAM, the faster some operations in L4 work. This is particularly true of indexing. Logos 4 is RAM and CPU intensive. And while there are some other unknowns in the mix, the more hardware you give L4 the better it will perform.

Keith Larson

https://community.logos.com/discussion/comment/45747#Comment_45747

This is a 64 bit Win 7 system. 4GB adds nothing to the cost. 6GB adds $150 to the cost and 8GB adds $250 to the cost. If indexing is the only thing that benifits from that added memory I am wondering if it is worth it.

Bohuslav Wojnar

https://community.logos.com/discussion/comment/45751#Comment_45751

This is a 64 bit Win 7 system. 4GB adds nothing to the cost. 6GB adds $150 to the cost and 8GB adds $250 to the cost. If indexing is the only thing that benifits from that added memory I am wondering if it is worth it.

Should help more things like multitasking etc.

Rich DeRuiter

https://community.logos.com/discussion/comment/45751#Comment_45751

This is a 64 bit Win 7 system. 4GB adds nothing to the cost. 6GB adds $150 to the cost and 8GB adds $250 to the cost. If indexing is the only thing that benifits from that added memory I am wondering if it is worth it.

How long to you plan to keep your computer? The longer you want to keep it, the more RAM you should get.

If upgrading your CPU to the next best is about the same price, I'd consider upgrading the CPU. Although both are critical, it's easier to replace RAM a year from now, and RAM should fall in price more than a CPU will. Besides that, some CPU upgrades may require a mother-board upgrade as well (unless you can look 'under the hood' there's no way to tell from an on-line compute seller). I have an Intel i7 920 with 6GB RAM and Logos flies (with a couple of odd exceptions). L4 is CPU intensive, and will make use of multi-core technology.

Keith Larson

https://community.logos.com/discussion/comment/45756#Comment_45756

This is actually a new laptop purchase. The CPU would be the i7-720QM. My present laptop is 3.5 years old and really does not run L4 well. I like to keep my laptops about 3 years and then look to upgrade. I have found adding memory to laptops usally requires you to waste the original memory, so I definately want to purchase the amount of memory I would be happy with over a three year period.

Rich DeRuiter

https://community.logos.com/discussion/comment/45767#Comment_45767

This is actually a new laptop purchase. The CPU would be the i7-720QM. My present laptop is 3.5 years old and really does not run L4 well. I like to keep my laptops about 3 years and then look to upgrade. I have found adding memory to laptops usally requires you to waste the original memory, so I definately want to purchase the amount of memory I would be happy with over a three year period.

With the price you were quoting for the RAM, I figured it probably was a laptop.

That's a pretty good CPU. i7's seem to work well with L4, from what I've seen in these forums. And faster CPU's create heat problems, especially in laptops.

If Logos is the heaviest hitter in your software arsenal, then 6GB is good enough, IMHO (though 8GB would give you a slight edge sometimes - in indexing for sure), and is probably the sweet spot (and 2X the recommended by the Logos Tech FAQ). Though I note that 8GB seems to be a better deal / GB.

I guess the only other issue is whether you have integrated or dedicated video. If it's integrated, then definitely go with 8GB. The recommended video RAM in the above tech FAQ is 512MB (min is 128MB); make sure you're getting that too.

David Miller

Getting more memory than you need is just a waste. How can you tell how much you are using? Fire up Task Manager and click the "Performance' tab. Look at "Peak Commit Charge". This is the maximum amount of RAM your system has needed since the last reboot.

Rich DeRuiter

https://community.logos.com/discussion/comment/45805#Comment_45805

Fire up Task Manager and click the "Performance' tab. Look at "Peak Commit Charge"

No such line on my task manager (Win7 64bit),

Keith Larson

https://community.logos.com/discussion/comment/45781#Comment_45781

I found a $400 off Black Friday coupon for the HP dv7t Quad. It has 1 GB dedicated card. The upgrade from 3GB memory to 4 GB memory is free, the 6GB memory upgrade is at a 25% discount and the 8GB memory is at a 50% discount. 3.5 years ago when I purchased my last laptop 1GB of memory seemed more than enough, but about two years ago I upgraded to 2GB and now that is totally inadiquate for L4. I don't want to spend more money than I have too, but I also don't want be penny wise but pound poor and find I need to upgrade my memory in a year or two.

Some other nice things about this laptop is they are offering a free upgrade to a larger Hard Drive and a Blue Ray DVD player.

I have had really good experience with HP laptops. This will be my fourth in a row. I loved all of them!

Rich DeRuiter

https://community.logos.com/discussion/comment/45811#Comment_45811

I found a $400 off Black Friday coupon for the HP dv7t Quad. It has 1 GB dedicated card. The upgrade from 3GB memory to 4 GB memory is free, the 6GB memory upgrade is at a 25% discount and the 8GB memory is at a 50% discount. 3.5 years ago when I purchased my last laptop 1GB of memory seemed more than enough, but about two years ago I upgraded to 2GB and now that is totally inadiquate for L4. I don't want to spend more money than I have too, but I also don't want be penny wise but pound poor and find I need to upgrade my memory in a year or two.

Some other nice things about this laptop is they are offering a free upgrade to a larger Hard Drive and a Blue Ray DVD player.

I have had really good experience with HP laptops. This will be my fourth in a row. I loved all of them!

Looks like a great deal. My philosphy is that my time is always more important than my money. While 6GB may be the sweet-spot today, 8GB may give you cushion for software 'bloat,' and allow a bit more head room for multi-tasking.

HP is a good, solid brand with a better service & support record than Dell.

Beware that there are still some unknowns in the L4 performance arena. Some with very high-end systems still do not have a great experience with L4. Wish we knew why.

Keith Larson

https://community.logos.com/discussion/comment/45819#Comment_45819

For those interested in this Black Friday deal here is the link to the coupon http://www.notebooks.com/2009/11/27/black-friday-400-off-hp-pavilion-dv7t-quad-edition/. For $899 this looks like a great laptop to run L4 on.

Matt

https://community.logos.com/discussion/comment/45831#Comment_45831

Keith, as another poster mentioned, it all depends on what else will be running along with Logos 4.

Logos 4 is a 32-bit application. By default, on a 32-bit or 64-bit OS a 32-bit application is given 2 GB of address space to work with (i.e. the rest of the virtual address space is given to the OS, in the 32-bit OS case, the upper 2 GB, and in the 64-bit OS case its the upper 2^63 - 2GB).

If Logos 4 is built with the linker flag LARGEADDRESSAWARE, then if a 32-bit system is booted with the /3GB boot.ini switch, then the process can utilize up to 3 GB of memory. If the OS is 64-bit, then if the linker flag is set, then the process is given 4 GB of address space.

I just checked the file header in the Logos4 executable, and the LARGEADRESSAWARE bit has not been set, which indicates that even if the image is launched in a 32-bit OS that has the /3GB switch in boot.ini or on a 64-bit OS, the process will *not* take advantage of the extra memory address space (this is unfortunate). All that being said, as I've watched the private bytes within the Logos4 process and the indexer process, I have never seen them top 1 GB of private bytes, so for now it's a moot point as it appears that Logos purposely only allows a certain memory footprint for resources. This is both good and bad: good because it demonstrates that they were conscientious and have a handle on their memory allocations, bad because they are not utilizing the memory and hardware of many of our systems to their potential.

Where things really slow down (memory access-wise) on a computer is when the system does not have enough RAM available to keep all of the resources within RAM and it must then page it out to disk (i.e. to the paging file). It is several orders of magnitude faster to access a resource that is resident in RAM as opposed to on disk (with the new solid state disks, this is not as true, but still slower). So, the question ultimately boils down to where we started:

If you have 4 GB of RAM, and Logos and the indexer together as separate processes will typically never use more than 2 GB of RAM together, you will have 2 GB of RAM for your OS and sundry other apps. If you don't feel your other applications that you'll want to have open at the same time as Logos will approach 2 GB, then 4 GB should be fine for you. If you want to have Photoshop, 50 browser windows open, Outlook and 10 other applications open, then you should go for 6 or 8 GB of RAM.

Matt

P.S. If anyone at Logos with dev knowledge is reading this: set the largeaddressaware flag in the linker, it's cheap and typically has no side effect! Then, when launching, check what system you're launching under, and if it's appropriate, use that memory to load resources! It would help (at least in the case of accessring resource data from disk) tremendously.

Keith Larson

https://community.logos.com/discussion/comment/45893#Comment_45893

Thanks Matt,

This was very helpful. It confirms what I have observed on my 4GB desktop system. When I am working on a sermon I will typically have L4, L3, MS Word, MS Outlook, and one browser window open and I never seem to come close to using all of this memory. I certainly don't notice the HD thrashing as Windows is accessing the page file. It would seem that unless Logos does as you are suggesting, 4GB is enough for the average user. I already ordered the laptop with more 8GB of memory, but I may call back and change my order. The order is not being built until December 9.