Yes. Smegma is right -- the problem is that Limewire scales very poorly, not that it doesn't perform well with a small load. Increase the hardware from your AMD 500MHz and 128 ram to something modern, and increase the demands you put on Limewire in proportion, and Limewire chokes. Somehow, either it doesn't utilize all the resources available, or it scales worse than linearly with the amount of files shared, amount of pending downloads, and such. Neither should be the case.

Actually, sorting would be a mild exception to that. Sort the download list by e.g. name and you should see n log n (at worst) scaling behavior, which is worse than linear but not, admittedly, by much. But the behavior Limewire exhibits here looks like it must be quadratic, or worse, or it wouldn't be notices. There's no excuse for quadratic scaling in this sort of application, and there's also no excuse for the user interface freezing or for it to hog the CPU even to the point of pre-empting higher priority tasks. I've seen it lock up a Windows machine myself -- even Task Manager wouldn't respond, and it had High priority and Limewire had Below Normal due to its having kept things like web surfing from being painless at Normal. When the system recovered, the Task Manager popped up and showed Limewire coming down from 100% cpu use, so there's little doubt as to who the culprit was.

The user interface event handling thread should not block waiting for anything, period. A task should never pre-empt anything with a higher priority, period. Quadratic or worse scaling behavior in this type of app is unacceptable, period. Something is very wrong here.

Dear Bucketofbolts:

LimeWire slows down my computer, too.

It is a heavy program that requires lots of resources. I am running Windows XP, and by using Ctrl-Alt-Del to open the Task Manager, I can see that LW places a heavy burden on my "commit cache."

I get the feeling that what you want to do is run LW in the background and still be able to do something else with your computer. The short answer is, you have to have a lot of computer in order to run LimeWire and still do other things.

My Dell computer came with lots of software loaded that I didn't need, and didn't want, and I have freed lots of memory by disabling or totally removing useless software. hkcmd.exe, for example, is an Intel program that is totally unnecessary, but to make it go away and release the memory that it occupied, I first had to discover what it was, and then disable it.

Most computer owners have software running that they neither need nor want, and this is especially true of us who bought a computer already preloaded with software. Off-the-shelf computers that seem like a bargain always have lots of preloaded software that place a burden on system resources, and what you have to do is decide which programs you want to keep and which you want to uninstall.

Get rid of the crap you don't want, and you'll find that your computer will stand up and do tricks that you didn't expect it could do.

So without even knowing what your particular situation is, Bucketofbolts, I suspect you have lots of programs running in the background, many of which you neither need nor want, that are slowing your computer down even before you try to load and run LimeWire.

My computer is a low-end, rather crappy thing, but I can run LimeWire, listen to music from ShoutCast, play a modest video game, explore my hard drive, and do all this without overheating my processor. I accomplished this by getting rid of the programs I didn't need and didn't want.

I hope this helps you somehow. I can't offer you specific help; it's more a general idea.

Donkeyboy

Yes. Smegma is right -- the problem is that Limewire scales very poorly, not that it doesn't perform well with a small load. Increase the hardware from your AMD 500MHz and 128 ram to something modern, and increase the demands you put on Limewire in proportion, and Limewire chokes.

Well I guess mabey you should read some of the forum post on setting up L/W. I once had the same problem and followed Lord Of The Rings Sugestions and cleared the problem up. And as far as modernizing you mabey you should learn how to configure L/W before you speak. I have used all the P2P software out there and L/W is the best of all. On my machine I have been downloading up to 7 files at one time at speeds of up to 300KB/s and up loading 2 files at 35KB/s in ultraper mode. As I am wrighting this I am DL 2 files at 150KB/s and UL 2 at 35KB/s and I leave L/W running for days at a time surf the web and play games like Half Life 2 at the same time. Not bad for a modern machine that chokes on L/W. My current ues is cpu 3% Mem 52440

AMD 64 3200+ overclocked 3.2 GHZ
1 GIG 3200 corsair ram
ASUS A8V Deluxe
EVGA e-GeForce 6200 NVIDIA
Adaptec 29320 SCSI U320 Adapter card
2-Fujitsu 15,000 RPM SCSI ULTRA 320 74 GB hard drives 0-Raid
1 WesternDigatal 120 GB
I would say I have a fairly modern machine and have no problem at all with L/W. So mabey you should try fixing your settings before you make coments like you made then mabey the rest of us wont know how much you really dont know.

Try listining to others and good luck

My setup is fine thank you very much. Ultrapeer disabled, no unnecessary tabs open, etc. -- the scaling behavior remains poor. There's no reason it should work fine with a few files pending, but bog down with a few hundred or more, on modern hardware. If a few pending files works on decade-old hardware a few hundred should work fine on modern hardware.

Well OK so you think it is a problem with L/W I do not think this is the case. I run L/W on 3 diffrent computers and it works fine on all 3 it uses between 3% & 5% of my cpu and 40,000k & 60,000k mem depending on how much UL & DL are going on weather I am in ultrapper moed etc, all are running L/W 4.9 and the latest java In the previous post I made a mistake on Ghz cpu is running
#1
AMD 64 3200+ overclocked 2.3 GHZ
1 GIG 3200 corsair ram
ASUS A8V Deluxe
EVGA e-GeForce 6200 NVIDIA
Adaptec 29320 SCSI U320 Adapter card
2-Fujitsu 15,000 RPM SCSI ULTRA 320 74 GB hard drives 0-Raid
1 WesternDigatal 120 GB
#2
AMD 2600+ overclocked 2 Ghz
1.5 Ghz kingston PC 2700
MSI K7N2 Delta
MSI GeForce 5200
1 WesternDigatal 120 GB
#3
Toshiba Laptop
Intel Celleron M 1.5 Ghz
768 MB Kingston Sodium
Intel extreme graphics

As you can se there is quite a bit of diffrence in these 3 machines but they all preforme fine with L/W running I am able to play games cruse the net or do whatever. I do notice a slight decline in the laptop but not much. So you can blamb L/W if you wish butt I think you are wrong. All the above machines are running XP Pro

Latter Grandpa

I've found the problem. Previous versions of Limewire didn't give a crap how many files were in your download directory, so long as you weren't sharing it.

4.9 does. And there were over 40,000 files in it (though only 499 shared).

Moving some of them and cutting it down to 20,000 produced a performance improvement. Moving more of them produced a bigger improvement.

Limewire's memory use shouldn't even be scaling with the size of a disk directory IMO -- that's the whole point of something being a disk directory, so that only some of it needs be referenced in memory at a time.

Limewire's CPU use certainly shouldn't be scaling with the size of a disk directory. It should only scale with actual activity -- user input, active uploads, active downloads, and active peer connections should contribute to CPU use, and nothing but these. Yet downloads "awaiting sources" still seem to contribute, and in 4.9 even unshared files sitting in the download destination folder seem to contribute.

LimeWire calculates cryptographic hashes for all of those files and stores them in RAM, which speeds up the process of sharing those files if you so choose. This is quite CPU intensive until all of the files in your download directory have been hashed.

Ideally, all filesystems would support rich metadata that would allow LimeWire to store the SHA-1 and Tiger tree as an attribute of each file. However, this is not the case, and storing this information in RAM is a nearly ideal solution for nearly all users.

For most users, this increases the speed with which they can share files and doesn't waste much RAM or CPU time on files that will never be shared. Your situation happens to be an extreme case, and your work-around is easy and effective.

Actually, the workaround doesn't work, unless I want to keep getting duplicate files. I have to leave a file there as long as I'm doing searches that might turn it up, or it won't show as something I already have.

I saw someone mention in a thread somewhere using zero length files of the same name. Would that avoid the problem? Hashing a zero length file shouldn't exactly take long. In fact Limewire ought sensibly to ignore such files except for the purposes of generating "file already exists, overwrite?" prompts.

That's the only way to keep track of a lot of files you already have without doing it in ram I think -- that or keeping the actual files themselves in the download directory indefinitely. Without either a duplicate hash or a duplicate file name Limewire will have no way of flagging duplicates in search results, and it seems keeping all the hashes of every file ever downloaded is prohibitively slow and expensive...

I have read this whole thread on system slowdown. I have a similiar problem but do not have high CPU utilization.
I have a 1.8 ghz p4 500 ram running xp pro and LW 4.8.1 pro, java 1.5.4 and cable connection.

I have have max uploads and downloads set to 4 and have followed the previous suggestions for LW setup.

LW runs about 4 to 15% cpu and 40,000 - 60,000 memory.

It seems to run fine when first started and then as the day goes on it progressively slows my machine down. Switching between active windows takes forever as the graphics slowly are displayed. The disk drive goes crazy like a lot a swapping is going on. Stuff is downloading great, but I sacriface using my machine for anything else because of the horrible performance.

It seems that one I switch to and active appplication, say Lotus notes, and it gets caught up, that app is runs better until you switch to another app.

It is really bad if you let it lock out from inactivity. It takes for ever for it to wake up and log back in.

The machine runs fine once I shut LW down. Azureus had the same problem but worse, that is why I tried LW.

There must be something we are missing here. Any suggestions?