16Gb RAM and page file...no help?

[Guest dbrentw]

I posted a question concerning my system configuration w/ 16GB RAM and the

issues I'm having w/ virtual memory, but I've received no help. No one has

any clues? This is critical for a potential customer. Any info would be

greatly appreciated.

 

Thanks

[Guest Charlie Russel - MVP]

Re: 16Gb RAM and page file...no help?

 

not seeing it, and haven't had any issues myself, nor seen any others

reported here. I'm running multiple servers with 16 GB of RAM.

 

--

Charlie.

http://msmvps.com/xperts64

http://mvp.support.microsoft.com/profile/charlie.russel

 

 

"dbrentw" <dbrentw@discussions.microsoft.com> wrote in message

news:F323C060-B1C1-4928-A476-DC06A5377137@microsoft.com...

>I posted a question concerning my system configuration w/ 16GB RAM and the

> issues I'm having w/ virtual memory, but I've received no help. No one has

> any clues? This is critical for a potential customer. Any info would be

> greatly appreciated.

>

> Thanks

[Guest dbrentw]

Re: 16Gb RAM and page file...no help?

 

Thanks for the reply Charlie.

 

Are you running any individual processes that require many GBs of data? This

problem is easily reproducible for me, although I've only tested it w/ the

Java application that we've developed.

 

BTW, if you mean "not seeing it" that you don't see the post, look for "16Gb

Ram and page file" from yesterday.

 

"Charlie Russel - MVP" wrote:

> not seeing it, and haven't had any issues myself, nor seen any others

> reported here. I'm running multiple servers with 16 GB of RAM.

>

> --

> Charlie.

> http://msmvps.com/xperts64

> http://mvp.support.microsoft.com/profile/charlie.russel

>

>

> "dbrentw" <dbrentw@discussions.microsoft.com> wrote in message

> news:F323C060-B1C1-4928-A476-DC06A5377137@microsoft.com...

> >I posted a question concerning my system configuration w/ 16GB RAM and the

> > issues I'm having w/ virtual memory, but I've received no help. No one has

> > any clues? This is critical for a potential customer. Any info would be

> > greatly appreciated.

> >

> > Thanks

>

[Guest Charlie Russel - MVP]

Re: 16Gb RAM and page file...no help?

 

I'm running about 9 Longhorn Server VMs and 4-8 XP/Vista clients. I've got a

large swap file (16, 681 MB) and haven't had performance issues. Of course,

this is a very good server, with a really good I/O subsystem. (HP ML350 G5

with a Smart Array P400 (512 Mb Cache), and 8x2.5" 15k SAS HDs.)

 

What I _do_ see is that at 12-13 GB of RAM utilization things slow down.

This is, IMHO, the limitation of the current Intel memory architecture,

which simply has too narrow a pipe to its Northbridge and RAM, and no

on-board memory controller. The quad-core procs, I'm told, can handle

considerably more RAM before they bog down.

 

--

Charlie.

http://msmvps.com/xperts64

http://mvp.support.microsoft.com/profile/charlie.russel

 

 

"dbrentw" <dbrentw@discussions.microsoft.com> wrote in message

news:C14C3078-D2D9-4C65-A58C-9940935402C4@microsoft.com...

> Thanks for the reply Charlie.

>

> Are you running any individual processes that require many GBs of data?

> This

> problem is easily reproducible for me, although I've only tested it w/ the

> Java application that we've developed.

>

> BTW, if you mean "not seeing it" that you don't see the post, look for

> "16Gb

> Ram and page file" from yesterday.

>

> "Charlie Russel - MVP" wrote:

>

>> not seeing it, and haven't had any issues myself, nor seen any others

>> reported here. I'm running multiple servers with 16 GB of RAM.

>>

>> --

>> Charlie.

>> http://msmvps.com/xperts64

>> http://mvp.support.microsoft.com/profile/charlie.russel

>>

>>

>> "dbrentw" <dbrentw@discussions.microsoft.com> wrote in message

>> news:F323C060-B1C1-4928-A476-DC06A5377137@microsoft.com...

>> >I posted a question concerning my system configuration w/ 16GB RAM and

>> >the

>> > issues I'm having w/ virtual memory, but I've received no help. No one

>> > has

>> > any clues? This is critical for a potential customer. Any info would be

>> > greatly appreciated.

>> >

>> > Thanks

>>

[Guest dbrentw]

Re: 16Gb RAM and page file...no help?

 

Well, it still doesn't make sense that I can run a process in about an hour

w/ no page file, using 5GB of physical memory, but run the same process in at

least several hours (I terminated it) where physical memory was capped at 1Gb.

 

What I want to see happen is the JVM grab 15GB of physical memory and use as

much of this as available. When physical RAM is almost used up, THEN the

system should start using the page file.

 

Call me crazy, but this seems the correct (and obvious) use of a page file.

 

Incidentally, I've run this same app on a Linux box WITH a page file, and it

performed as expected.

[Guest Mach58]

Re: 16Gb RAM and page file...no help?

 

On Thu, 8 Nov 2007 17:39:00 -0800, dbrentw

<dbrentw@discussions.microsoft.com> wrote:

>Well, it still doesn't make sense that I can run a process in about an hour

>w/ no page file, using 5GB of physical memory, but run the same process in at

>least several hours (I terminated it) where physical memory was capped at 1Gb.

>

>What I want to see happen is the JVM grab 15GB of physical memory and use as

>much of this as available. When physical RAM is almost used up, THEN the

>system should start using the page file.

>

>Call me crazy, but this seems the correct (and obvious) use of a page file.

>

>Incidentally, I've run this same app on a Linux box WITH a page file, and it

>performed as expected.

 

 

Don't have any experience with Java (I'm a C# guy), but I found this

link:

 

http://rsb.info.nih.gov/ij/docs/install/windows.html#w64

 

which may or may not help. Your problem is that you want to manage

memory yourself, but the JVM doesn't let you do it. In the unmanaged

world, there's kernel32's VirtualLock, which lets you specify ranges

of memory that shouldn't get paged out.

 

HTH,

Mach

[Guest dbrentw]

Re: 16Gb RAM and page file...no help?

 

Ok, I feel like I need to go on record and say that the issue was MY FAULT.

 

It appears that I was testing the app 2 different ways: from a batch file

and from command line. Well, it turns out that in the .bat file, I had the

memory options at the end of the command instead of before the -jar

option...well, if you do this, you don't actually set the JVM to use the

options that you specify!!

 

I was running it correctly from the command line, which is why I saw the

correct performance those times.

 

STUPID! Oh well, live and learn. Thanks to those who responded. Cheers.

[Guest Tony Sperling]

Re: 16Gb RAM and page file...no help?

 

 

"dbrentw" <dbrentw@discussions.microsoft.com> wrote in message

news:CE94A060-C865-49D6-995B-0017195B6DD6@microsoft.com...

 

<

<. . .the issue was MY FAULT.

<

 

Welcome to the Club!

 

 

Tony. . .