return totalAllocated.get() - totalReleased.get();
    }

    /**
     * Get number of available send regions in pool
     *
     * @return available send regions
     */
    public int getAvailableSendRegions() {
        return availableSendRegions.size();
    }

    /**
     * Get number of available receive regions in pool
     *
     * @return available receive regions
     */