<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta http-equiv="Content-Type" content="text/html;charset=ISO-8859-1"> <title></title> </head> <body text="#000000" bgcolor="#ffffff"> Sounds like you could treat /dev/shm as a large, linear file and mmap() one window into it at a time... Chris Kloiber wrote: <blockquote type="cite" cite="mid1070987986.25397.111.camel@outhouse.rdu.redhat.com"> <pre wrap="">On Tue, 2003-12-09 at 08:16, James Olin Oden wrote: </pre> <blockquote type="cite"> <pre wrap="">On Mon, 8 Dec 2003, Vanco, Don wrote: </pre> <blockquote type="cite"> <pre wrap="">While I hate to use this as a support line I've gotten no help from the 2 local lugs I've queried, and know that there's some heavy hitters lurking here. I understand that the Linux kernel can (through PAE) provide memory paging beyond 4GB of physical memory on 32-bit architecture. What I need to understand is: what are the requirements on the application side to utilize this memory? I'm looking for documentation / links that talk about applications and PAE. Case in point: Lotus Notes on OS400 can address huge amount of RAM, but when it's running on Linux does it need to be compiled in a specific manner, or with some specific bit of code / API to address more than the architecture physically supports? </pre> </blockquote> <pre wrap="">Hi Don, We use the PAE feature where I work. The deal is that this functionality only makes it possible for the kernel to access and use all this memory, but each process still can only address 4Gig of memory less the amount of memory under 4Gig the kernel is using. If you wanted a single app to use more than 4Gig, at this point you would need to create several processes that share memory. Even this this is very specific to the application as to whether such a scheme could be used effectively (you would in effect be shuffling data around processes as needed). Does anyone know of any other solutions than PAE? </pre> </blockquote> <pre wrap=""> Can you do some tricks like Oracle does? They can use very large shared memory segments using /dev/shm I've seen customers use /dev/shm up to 6 gigs on a 8 Gig box, and 14 Gigs on a 16 Gig box. This is probably slower than normal ram access, but faster than swapping to disk. Remember I'm in Support, I can't help you program this. </pre> </blockquote> </body> </html>