samba memory utilization, writeback - and loopback mounts

[Steven French]

This patch describes a "fix" to linux to reduce the hangs which can occur
in mounts over loopback to nfs server
      http://linux.bkbits.net:8080/linux-2.6
/gnupatch at 3ee6d5caVqF30UJO9OB_iSm6LvtHMQ
This changes the behavior of balance_dirty_pages when running under the
file server.

The same could presumably occur when cifs (or smbfs) mounted to samba, and
probably does hit every once in a while based on testing reports, but this
could be harder for Samba to set (the flag PF_LESS_THROTTLE) for smbd
processes in user space.

Ideas?

Steve French
Senior Software Engineer
Linux Technology Center - IBM Austin
phone: 512-838-2294
email: sfrench at-sign us dot ibm dot com