Network problems while running VirtualBox

[Peter Ross]

Quoting "Adam Vande More" <amvandemore at gmail.com>:

> On Wed, Jul 13, 2011 at 6:57 PM, Peter Ross
> <Peter.Ross at bogen.in-berlin.de>wrote:
>
>> Hi all,
>>
>> I have a problem with the network while running VirtualBox.
>>
>> As soon as I _run_ a VirtualBox I am not able to copy large files (e.g.
>> virtual disks or ZFS snapshots) using ssh/scp to another machine.
>>
>> The ssh crashes with "Write failed: Cannot allocate memory"
>> <snip>
>> At the moment it is a real showstopper for running VirtualBox/FreeBSD
>> production because I cannot backup VirtualBoxes. Mahlon gave up on it and
>> uses Citrix by now (but is still keen to have this solved).
>>
>> Any idea what causes the problem? I am happy to gather information,
>> applying patches etc. if it helps.
>>
>
> Just a thought, does using ssh from ports make any difference?

I am running named on the same box. I have overtime some errors there as well:

Apr 13 05:17:41 bind named[23534]: internal_send:  
192.168.50.145#65176: Cannot allocate memory
Jun 21 23:30:44 bind named[39864]: internal_send:  
192.168.50.251#36155: Cannot allocate memory
Jun 24 15:28:00 bind named[39864]: internal_send:  
192.168.50.251#28651: Cannot allocate memory
Jun 28 12:57:52 bind named[2462]: internal_send: 192.168.165.154#1201:  
Cannot allocate memory
Jul 13 19:43:05 bind named[4032]: internal_send:  
192.168.167.147#52736: Cannot allocate memory

coming from a sendmsg(2).

My theory there is: my scp sends a lot data at the same time while the  
named is sending a lot of data over time - both increasing the  
likelyhood of the error.

>  Do you have
> any more info about the threshold of file size for when this problem starts
> occurring?  is it always the same?

No, it varies. Usually after a few GB. E.g. he last one lasted 11GB  
but I had failures below 8GB transfer before.

The system itself is quite stable regarding running processes and  
memory usage otherwise, here the description of it:

This machine is running:

- DHCP server (host)
- NTP server (host)
- Nagios monitor (nagios jail)
- DNS server (bind jail)
- MySQL server (mysql jail)
- Apache server with ITWiki (apache jail)
- Admin mail server (adminmail jail)
- Zimbra 7.0 Mail server (zimbra VirtualBox)

The machine has 8GB of RAM, and the footprint of the jails is minimal  
(the MySQL server is for the mediawiki only which is used by two  
people at the moment and not heavily).

Here a top(1) sorted by size:

last pid: 30169;  load averages:  0.38,  0.41,  0.41    up 8+19:04:43   
11:51:39
159 processes: 1 running, 158 sleeping
CPU:  0.4% user,  0.0% nice,  0.4% system,  0.0% interrupt, 99.2% idle
Mem: 84M Active, 356M Inact, 4516M Wired, 1004K Cache, 33M Buf, 2943M Free
Swap: 8188M Total, 8188M Free

   PID USERNAME    THR PRI NICE   SIZE    RES STATE   C   TIME   WCPU COMMAND
92688 root         24  44    0  2078M  1991M IPRT S  8  18.3H  5.86%  
VBoxHeadle
  4768     88       16  51    0   213M 21672K sigwai  8   2:02  0.00% mysqld
57180 www           1  46    0   140M 10344K accept  3   0:00  0.00% httpd
  6223 www           1  76    0   139M  2400K accept 14   0:09  0.00% httpd
78674 www           1  44    0   138M 27056K accept  9   0:02  0.00% httpd
78924 www           1  44    0   138M 25928K accept  8   0:02  0.00% httpd
36114 www           1  44    0   138M 25424K accept  2   0:01  0.00% httpd
  3997 www           1  44    0   138M 25180K accept  1   0:00  0.00% httpd
57410 www           1  44    0   138M 24476K accept  8   0:01  0.00% httpd
48202 www           1  44    0   138M 18488K accept 10   0:00  0.00% httpd
29695 www           1  44    0   134M  4920K accept  8   0:00  0.00% httpd

> EG if Vbox has 2 GB mapped out and you
> get an error at a certain file size, does reducing the Vbox memory footprint
> allow a larger file to be successfully sent?

Given that the amount of data is randomly just now I cannot imagine  
how to get reliable numbers in this experiment.

While I am doing it I monitored the memory usage using top and vmstat  
but there does not seem to be a shortage.

I also tried lookbusy to occupy 2GB when VisualBox wasn't running. I  
even put slightly more pressure on it as VirtualBox does (that means  
the free memory was below the typical numbers when VirtualBox was  
running) - but the result is the same:

It works as long as I do not start the VirtualBox.

Regards
Peter