[linux-lvm] creation of snapshot fail somtimes w/ "Cannot allocate memory"

[Yedidia Klein]

Hello,

I've a daily snapshot that cron umount, delete, recreate and mount every 
night.
sometimes (about once a week) I'm getting the following output:

  Logical volume "daily" successfully removed
  device-mapper ioctl cmd 9 failed: Cannot allocate memory
  Couldn't load device 'ext-daily'.
  Problem reactivating origin part1
mount: special device /dev/ext/daily does not exist


mean that the umount and delete worked but the recreation and therefor 
the mount failed...
how could this be debugged ? any idea what could be the problem ?

thanks,

--Yedidia