Hi all,
I just compiled 2.4.14-pre8, did some bonnie++ runs
and compiled a few kernels to stress test this release.
Here's the output of 'free':
[root@tony] free
total used free shared buffers cached
Mem: 513336 82124 431212 0 30696 4294958092
-/+ buffers/cache: 60632 452704
Swap: 786416 4936 781480
cheers,
Patrick
Patrick Mau wrote:
>
> Hi all,
>
> I just compiled 2.4.14-pre8, did some bonnie++ runs
> and compiled a few kernels to stress test this release.
>
> Here's the output of 'free':
>
> [root@tony] free
> total used free shared buffers cached
> Mem: 513336 82124 431212 0 30696 4294958092
> -/+ buffers/cache: 60632 452704
> Swap: 786416 4936 781480
>
It's a bug in the /proc code. If buffercache pages exceed
pagecache pages, `pg_size' flips negative.
There doesn't seem to be any reason to subtract buffermem_pages
from page_cache_size - they're independent.
--- linux-2.4.14-pre8/fs/proc/proc_misc.c Tue Oct 23 23:09:42 2001
+++ linux-akpm/fs/proc/proc_misc.c Sun Nov 4 10:10:18 2001
@@ -140,7 +140,7 @@ static int meminfo_read_proc(char *page,
{
struct sysinfo i;
int len;
- int pg_size ;
+ unsigned int cached;
/*
* display in kilobytes.
@@ -149,14 +149,14 @@ static int meminfo_read_proc(char *page,
#define B(x) ((unsigned long long)(x) << PAGE_SHIFT)
si_meminfo(&i);
si_swapinfo(&i);
- pg_size = atomic_read(&page_cache_size) - i.bufferram ;
+ cached = atomic_read(&page_cache_size);
len = sprintf(page, " total: used: free: shared: buffers: cached:\n"
"Mem: %8Lu %8Lu %8Lu %8Lu %8Lu %8Lu\n"
"Swap: %8Lu %8Lu %8Lu\n",
B(i.totalram), B(i.totalram-i.freeram), B(i.freeram),
B(i.sharedram), B(i.bufferram),
- B(pg_size), B(i.totalswap),
+ B(cached), B(i.totalswap),
B(i.totalswap-i.freeswap), B(i.freeswap));
/*
* Tagged format, for easy grepping and expansion.
@@ -182,7 +182,7 @@ static int meminfo_read_proc(char *page,
K(i.freeram),
K(i.sharedram),
K(i.bufferram),
- K(pg_size - swapper_space.nrpages),
+ K(cached - swapper_space.nrpages),
K(swapper_space.nrpages),
K(nr_active_pages),
K(nr_inactive_pages),
Andrew Morton wrote:
>
> It's a bug in the /proc code. If buffercache pages exceed
> pagecache pages, `pg_size' flips negative.
>
> There doesn't seem to be any reason to subtract buffermem_pages
> from page_cache_size - they're independent.
>
Well that was crap, wasn't it? Wrong kernel.
I wonder if it's due to the fact that grow_dev_page()
calls find_or_create_page(), but we increment the
buffermem_pages count unconditionally, whether or
not the page was newly created?
On Sun, Nov 04, 2001 at 10:59:21AM -0800, Andrew Morton wrote:
> Andrew Morton wrote:
> >
> > It's a bug in the /proc code. If buffercache pages exceed
> > pagecache pages, `pg_size' flips negative.
> >
> > There doesn't seem to be any reason to subtract buffermem_pages
> > from page_cache_size - they're independent.
> >
>
> Well that was crap, wasn't it? Wrong kernel.
Hallo Andrew,
I didn't even noticed, because I had no time to test ;o)
But thnks anyway. Maybe - for testing only - one could insert
a BUG() if the cached amount gets negative to get a call trace ?
My expirience in kernel hacking is rather limited.
I just wanted to report it anyway, because I thought it got fixed.
Have a nice Monday,
(at least I hope I will),
Patrick