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

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dbrentw

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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
 
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
 
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
>
 
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
>>
 
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.
 
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
 
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.
 
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. . .
 
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