Irqbalance contains a bug in 1.0.4 which causes a memory leak on systems where /sys/bus/pci/devices is not available, such as on some virtual machines. The problem has been filed and a solution is available from irqbalance by simply updating to the latest version of irqbalance - v1.0.8
The issue was resolved upstream but the patch does not apply to 1.0.4:
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.