01-08-2009
try using the hugemem kernel
I believe starting the RHEL3 RedHat offers a hugemem kernel supports a 4GB per process user space and a 4GB direct kernel space. The hugemem kernel allows systems with up to 64GB of main memory and is required in order to use all the memory in system configured with more than 16GB of memory.
10 More Discussions You Might Find Interesting
1. UNIX for Dummies Questions & Answers
I wish to install Red Hat linux 7.1 on a machine with 16mb of EDO Ram. When I enter the instalation process I am told 'You do not have enough memory'. Is there a way to install RHL with only the 16? Or will I have to upgrade and buy some very expensive EDO.
~ Paul (3 Replies)
Discussion started by: KrazyGuyPaul
3 Replies
2. Debian
Hello all
i own p100 16ram laptop , i would like to run linux on it
i need it for gcc compilation and shell scripting , no gui.
what version of linux should i install , i dont mind to install old one .
tnx allot (5 Replies)
Discussion started by: umen
5 Replies
3. Solaris
What command should I be using on Solaris 9 to get an accurate representation of the available physical RAM? (4 Replies)
Discussion started by: dangral
4 Replies
4. Shell Programming and Scripting
Hi Gurus,
Can someone let me know how to find the RAM size,ROM size and Number of processors for a linux server.
Version :Linux 2.4.9-e.57smp
Also what does "e.57smp" stands for?
Thanks in advance gurus.....
cheers. (3 Replies)
Discussion started by: navojit dutta
3 Replies
5. Solaris
Hi All,
I am trying to find the physical memory usage by each process/users.
Can you please let me know how to get the memory usage?.
Thanks,
bsraj. (12 Replies)
Discussion started by: bsrajirs
12 Replies
6. Solaris
I have a Sun T5120, and I want to programmatically determine how much RAM it has.
# uname -a
SunOS myhost 5.10 Generic_141444-09 sun4v sparc SUNW,SPARC-Enterprise-T5120
The box has 64Gb; I tried prtdiag and prtconf, but they give me bogus info
prtconf gives me:
# prtconf |grep -i... (12 Replies)
Discussion started by: thomn8r
12 Replies
7. Cybersecurity
void main() {
long ((long)(&array));
int x;
for (;;)
{
(array) =+ 1023;
printf("%c", array);
}
}
What is wrong with this code to print Linux RAM? (13 Replies)
Discussion started by: Alux
13 Replies
8. Red Hat
Hi,
I have a server (BL460c) with 32G of physical RAM.
It currently only uses approx 5% its capacity but will use more (not sure how much more) pending the launch of further applications.
If I need to build another node of similar functionality should I consider downgrading the physical... (2 Replies)
Discussion started by: Duffs22
2 Replies
9. Solaris
Hi,
kstat -p -m zfs -n arcstats -s size returns
zfs:0:arcstats:size 8177310584
this values is approx (7.61 GB)
but my Physical Memory size is only 6144 Megabytes.
Can this happen ?
if yes, then how can I find free memory on the system.
BTW, I ran the kstat commands from a Non... (2 Replies)
Discussion started by: sapre_amit
2 Replies
10. Red Hat
Dear Expert,
I 've installed Redhat linux AS3, My machine having Inbuild network card (Intel(R) 82566DM-2 Gigabit Network Connection).
I've downloaded e1000e-2.3.2 from Intel site, but its not working for my machine. I'm unable to configure the Network.
ifconfig eth0 xx.xx.xx.xx netmask... (0 Replies)
Discussion started by: Mohammed Faiz
0 Replies
LEARN ABOUT DEBIAN
sf_buf_free
SF_BUF(9) BSD Kernel Developer's Manual SF_BUF(9)
NAME
sf_buf -- manage temporary kernel address space mapping for memory pages
SYNOPSIS
#include <sys/sf_buf.h>
struct sf_buf *
sf_buf_alloc(struct vm_page *m, int flags);
void
sf_buf_free(struct sf_buf *sf);
vm_offset_t
sf_buf_kva(struct sf_buf *sf);
struct vm_page *
sf_buf_page(struct sf_buf *sf);
DESCRIPTION
The sf_buf interface, historically the sendfile(2) buffer interface, allows kernel subsystems to manage temporary kernel address space map-
pings for physical memory pages. On systems with a direct memory map region (allowing all physical pages to be visible in the kernel address
space at all times), the struct sf_buf will point to an address in the direct map region; on systems without a direct memory map region, the
struct sf_buf will manage a temporary kernel address space mapping valid for the lifetime of the struct sf_buf.
Call sf_buf_alloc() to allocate a struct sf_buf for a physical memory page. sf_buf_alloc() is not responsible for arranging for the page to
be present in physical memory; the caller should already have arranged for the page to be wired, i.e., by calling vm_page_wire(9). Several
flags may be passed to sf_buf_alloc():
SFB_CATCH Cause sf_buf_alloc() to abort and return NULL if a signal is received waiting for a struct sf_buf to become available.
SFB_NOWAIT Cause sf_buf_alloc() to return NULL rather than sleeping if a struct sf_buf is not immediately available.
SFB_CPUPRIVATE Cause sf_buf_alloc() to only arrange that the temporary mapping be valid on the current CPU, avoiding unnecessary TLB shoot-
downs for mappings that will only be accessed on a single CPU at a time. The caller must ensure that accesses to the virtual
address occur only on the CPU from which sf_buf_alloc() was invoked, perhaps by using sched_pin().
Call sf_buf_kva() to return a kernel mapped address for the page.
Call sf_buf_page() to return a pointer to the page originally passed into sf_buf_alloc().
Call sf_buf_free() to release the struct sf_buf reference. The caller is responsible for releasing any wiring they have previously acquired
on the physical page; sf_buf_free() releases only the temporary kernel address space mapping, not the page itself.
Uses of this interface include managing mappings of borrowed pages from user memory, such as in zero-copy socket I/O, or pages of memory from
the buffer cache referenced by mbuf external storage for sendfile(2).
SEE ALSO
sendfile(2), vm_page_wire(9)
AUTHORS
The struct sf_buf API was designed and implemented by Alan L. Cox. This manual page was written by Robert N. M. Watson.
BSD
January 28, 2007 BSD