Re: [patch] 2.6.8.1: display committed memory limit and availablein meminfo

[Frank Hirtz]

> > The following patch will have the committed memory limit (per the 
> > current overcommit ratio) and the amount of memory remaining under 
> > this limit displayed in meminfo.
> >
> > It's presently somewhat difficult to use the strict memory overcommit 
> > settings as it's somewhat difficult to determine the amount of memory 
> > remaining under the cap. This patch would make using strict overcommit 
> > a good bit simpler. Does such an addition seem reasonable?
> >
> > Thank you,
> >
> > Frank.
Frank Hirtz wrote:
> Hi,
>
> I'm new to the list, and was wondering since I've not seen any feedback
> on this patch whether that was because the patch is not good/a good idea
> or whether no one has an opinion on displaying this information. I'd
> like to get this included and any feedback would be greatly appreciated.
>
> Thanks again,
>
> Frank.
>

Hearing no feedback on this, I'd like to request that this patch be included in 
the stock kernel release. As always, any feedback is appreciated.

Thank you again,

Frank.
--- linux-2.6.8.1/fs/proc/proc_misc.c		2004-08-18 16:32:07.000000000 -0400
+++ linux-2.6.8.1.new/fs/proc/proc_misc.c	2004-08-18 16:55:47.000000000 -0400
@@ -153,7 +153,7 @@
 				 int count, int *eof, void *data)
 {
 	struct sysinfo i;
-	int len, committed;
+	int len, committed, allowed;
 	struct page_state ps;
 	unsigned long inactive;
 	unsigned long active;
@@ -171,6 +171,8 @@
 	si_meminfo(&i);
 	si_swapinfo(&i);
 	committed = atomic_read(&vm_committed_space);
+	allowed = ((totalram_pages - hugetlb_total_pages()) 
+		* sysctl_overcommit_ratio / 100) + total_swap_pages;
 
 	vmtot = (VMALLOC_END-VMALLOC_START)>>10;
 	vmi = get_vmalloc_info();
@@ -198,7 +200,9 @@
 		"Writeback:    %8lu kB\n"
 		"Mapped:       %8lu kB\n"
 		"Slab:         %8lu kB\n"
+		"CommitLimit:  %8lu kB\n"
 		"Committed_AS: %8u kB\n"
+		"CommitAvail:  %8ld kB\n"
 		"PageTables:   %8lu kB\n"
 		"VmallocTotal: %8lu kB\n"
 		"VmallocUsed:  %8lu kB\n"
@@ -220,7 +224,9 @@
 		K(ps.nr_writeback),
 		K(ps.nr_mapped),
 		K(ps.nr_slab),
+		K(allowed),
 		K(committed),
+		K(allowed - committed),
 		K(ps.nr_page_table_pages),
 		vmtot,
 		vmi.used,