kernel memory limits

kernel memory limits

[Nick Burrett]

Hi,

I'm running standard 2.4.22 kernel, 2xP4 Xeon with 2Gb RAM.

After reaching 127 filesystems on the server, all formatted as reiserfs, 
I now find the following errors are occurring:


reiserfs: found format "3.6" with standard journal
reiserfs: using ordered data mode
loop(7,124):clm-2000, unable to allocate bitmaps for journal lists
Unable to handle kernel NULL pointer dereference at virtual address 00000000
  printing eip:
c01d5397
*pde = 00000000
Oops: 0000
CPU:    0
EIP:    0010:[<c01d5397>]    Not tainted
EFLAGS: 00010202
eax: 00000000   ebx: fdfe6100   ecx: fdfe6100   edx: e977c000
esi: 00000001   edi: 00000000   ebp: f1b37400   esp: d7d7fd88
ds: 0018   es: 0018   ss: 0018
Process mount (pid: 11157, stackpage=d7d7f000)
Stack: c91f3780 fdfe6100 00000001 f1b37400 fdfe6100 c01d5445 f1b37400 
fdfe6100
        00000008 00000001 00000000 c01d558a f1b37400 fdfe60e8 00000163 
00000001
        00000003 fdfe6000 e977c000 00000001 f1b37400 c01d8fb7 f1b37400 
fdfe60e8
Call Trace:    [<c01d5445>] [<c01d558a>] [<c01d8fb7>] [<c011c240>] 
[<c01c8902>]
   [<c0144afa>] [<c0145508>] [<c0145891>] [<c015b4f3>] [<c015b820>] 
[<c015b669>]
   [<c015bd0f>] [<c010770f>]

Code: 8b 34 b8 85 f6 74 59 8b 85 08 01 00 00 ff 88 bc 00 00 00 8b
  reiserfs: found format "3.6" with standard journal
reiserfs: using ordered data mode
loop(7,125):journal-1256: unable to get memory for journal structure
loop(7,125):sh-2022: reiserfs_read_super: unable to initialize journal space


Unfortunately I cannot decode the OOPS because kernel symbols don't 
appear to be exported on kernels with no loadable module support.

I also start to see errors like:

$ iptables -F
iptables: Memory allocation problem

I was hoping to mount 254 filesystems on this server.  Another server 
running ext2 successfully runs with over 1000 filesystems and another 
with ext3 runs 220 filesystems.

This is 100% reproducable. Is there anything I can do about this ?


Regards,


Nick.


-- 
Nick Burrett
Network Engineer, Designer Servers Ltd.   http://www.dsvr.co.uk

Re: kernel memory limits

[Nikita Danilov]

Nick Burrett writes:
 > 
 > 
 > Hi,
 > 
 > I'm running standard 2.4.22 kernel, 2xP4 Xeon with 2Gb RAM.
 > 
 > After reaching 127 filesystems on the server, all formatted as reiserfs, 
 > I now find the following errors are occurring:
 > 
 > 
 > reiserfs: found format "3.6" with standard journal
 > reiserfs: using ordered data mode
 > loop(7,124):clm-2000, unable to allocate bitmaps for journal lists
 > Unable to handle kernel NULL pointer dereference at virtual address 00000000
 >   printing eip:

Sorry, for delay.

Please try following patch:
----------------------------------------------------------------------

diff -puN fs/reiserfs/journal.c~jb_bitmaps-NULL-check fs/reiserfs/journal.c
--- i386/fs/reiserfs/journal.c~jb_bitmaps-NULL-check	Wed Nov 26 16:03:56 2003
+++ i386-god/fs/reiserfs/journal.c	Wed Nov 26 16:03:56 2003
@@ -193,6 +193,9 @@ static int set_bit_in_list_bitmap(struct
 static void cleanup_bitmap_list(struct super_block *p_s_sb,
                                 struct reiserfs_list_bitmap *jb) {
   int i;
+  if (jb->bitmaps == NULL)
+    return;
+
   for (i = 0 ; i < SB_BMAP_NR(p_s_sb) ; i++) {
     if (jb->bitmaps[i]) {
       free_bitmap_node(p_s_sb, jb->bitmaps[i]) ;

_
----------------------------------------------------------------------

(It is against 2.6, but hopefully will apply.)

Chris what do you think?

 > c01d5397

[...]

 > 
 > $ iptables -F
 > iptables: Memory allocation problem
 > 
 > I was hoping to mount 254 filesystems on this server.  Another server 
 > running ext2 successfully runs with over 1000 filesystems and another 
 > with ext3 runs 220 filesystems.
 > 
 > This is 100% reproducable. Is there anything I can do about this ?
 > 

Patch should fix the oops, but not the memory exhaustion problem.

 > 
 > Regards,
 > 
 > 
 > Nick.
 > 

Nikita.

 > 
 > -- 
 > Nick Burrett
 > Network Engineer, Designer Servers Ltd.   http://www.dsvr.co.uk
 >