Re: Why does the kernel need a gig of VM?

2005-02-01 Thread Bill Davidsen
John Richard Moser wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Wow. I'd heard that there was a way to set 3.5/0.5 GiB split, and that there was a patch that removed the split and isolated the kernel (but that was slow), so I was just curious about all this stuff with people screaming about

Re: Why does the kernel need a gig of VM?

2005-01-29 Thread Chris Friesen
John Richard Moser wrote: So what's the layout of that top 1G? What's it all used for? Is there some obscene restriction of 1G of shared memory or something that gets mapped up there? How much does it need, and why? What, if anything, is variable and likely to do more than 10 or 15 megs of varia

Re: Why does the kernel need a gig of VM?

2005-01-28 Thread Andy Isaacson
On Fri, Jan 28, 2005 at 03:06:15PM -0500, John Richard Moser wrote: > Can someone give me a layout of what exactly is up there? I got the > basic idea > > K 4G > A 3G > A 2G > A 1G > > App has 3G, kernel has 1G at the top of VM on x86 (dunno about x86_64). > > So what's the layout of that top 1

Re: Why does the kernel need a gig of VM?

2005-01-28 Thread Oliver Neukum
Am Freitag, 28. Januar 2005 21:42 schrieb Josh Boyer: > Because of various reasons.  Normal kernel space virtual addresses > usually start at 0xc000, which is where the 3GiB userspace > restriction comes from.   > > Then there is the vmalloc virtual address space, which usually starts at > a h

Re: Why does the kernel need a gig of VM?

2005-01-28 Thread John Richard Moser
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Wow. I'd heard that there was a way to set 3.5/0.5 GiB split, and that there was a patch that removed the split and isolated the kernel (but that was slow), so I was just curious about all this stuff with people screaming about how tight 4G of VM is v

Re: Why does the kernel need a gig of VM?

2005-01-28 Thread Josh Boyer
On Fri, 2005-01-28 at 15:06 -0500, John Richard Moser wrote: > -BEGIN PGP SIGNED MESSAGE- > Hash: SHA1 > > Can someone give me a layout of what exactly is up there? I got the > basic idea > > K 4G > A 3G > A 2G > A 1G > > App has 3G, kernel has 1G at the top of VM on x86 (dunno about x8

Why does the kernel need a gig of VM?

2005-01-28 Thread John Richard Moser
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Can someone give me a layout of what exactly is up there? I got the basic idea K 4G A 3G A 2G A 1G App has 3G, kernel has 1G at the top of VM on x86 (dunno about x86_64). So what's the layout of that top 1G? What's it all used for? Is there some